Aldh-2 inhibitor compounds and methods of use

ABSTRACT

Disclosed herein are aldehyde dehydrogenase (ALDH-2) inhibitor compounds, such as a compounds of Formula (I) or Formula (II), pharmaceutical compositions comprising these inhibitor compounds, and uses of these compounds and compositions, such as in the methods for safely treating chemical dependency on a substance or condition of addiction, such as alcohol, nicotine, cocaine, opiates, amphetamines, and compulsive eating disorder, and/or anxiety disorder, each individually or concurrent.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority of U.S. Provisional Patent ApplicationNo. 63/352,002, filed Jun. 14, 2022, the entirety of which is herebyincorporated by reference herein.

FIELD

The present disclosure relates to novel compounds that selectivelyinhibit aldehyde dehydrogenase-2 (ALDH-2). The disclosure also relatesto pharmaceutical compositions that include the inhibitor compounds anduses of the compounds or compositions in methods for safely treatingchemical dependency on a substance or condition of addiction, such asalcohol, nicotine, cocaine, opiates, amphetamines, and compulsive eatingdisorder, and/or anxiety disorder, each individually or concurrent.

BACKGROUND

Addiction remains a major health problem around the world. The UnitedStates Surgeon General has declared substance abuse a national healthcare crisis that is estimated to have resulted in greater than 3 monthsreduction in average U.S. life expectancy, 155,000 related deaths peryear, 23 million needing treatment, and a $400 billion economic costannually. See “Facing Addiction in America,” Surgeon General's Report,2016. The Center for Disease Control estimates that illicit drugoverdoses killed 64,000 people in the U.S. in 2016, with 14,000 of thosedeaths resulting from prescription opioid medications.

Inhibition of aldehyde dehydrogenase-2 (ALDH-2) has been shown to reducepathophysiologic dopamine surge without changing basal dopamine levelsin a rat model of cue-induced cocaine relapse-like behavior. See e.g.,Yao et al., “Inhibition of aldehyde dehydrogenase-2 suppresses cocaineseeking by generating THP, a cocaine use-dependent inhibitor of dopaminesynthesis,” Nature Medicine (2010), Vol. 16, No. 9; Diamond and Yao,“From Ancient Chinese Medicine to a Novel Approach to Treat CocaineAddiction,” CNS & Neurological Disorders—Drug Targets (2015) Vol. 14,No. 6. A recent review concludes that dopamine surge above normal levelsis part of the reward circuit common to all drugs of addiction. Seee.g., Volkow et al., “Neurobiologic Advances from the Brain DiseaseModel of Addiction,” N. Engl. J. Med. (2016) 374:363-371.

A genus of compounds with a structural core related to2,6-dichloro-N-[4-(2-oxo-1,2-dihydro-pyridin-4-yl)-benzyl]-benzamidehave been shown to inhibit ALDH-2 selectively relative to the monoamineoxidase (MAO) pathway, and exhibit effectiveness in treating rat modelsof alcohol, nicotine, and cocaine dependency. See e.g., U.S. Pat. Nos.8,558,001, 8,575,353, 9,000,015, 9,610,299; Int'l Pat. Publ.WO2013/006400; and Rezvani et al., “Inhibition of AldehydeDehydrogenase-2 (ALDH-2) Suppresses Nicotine Self-Administration inRats,” (2015) Journal of Drug and Alcohol Research, vol. 4: 1-6. Thecompound2,6-dichloro-N-[4-(2-oxo-1,2-dihydro-pyridin-4-yl)-benzyl]-benzamide,however, has been found to exhibit high levels of hepatotoxicity inhumans. See e.g., O'Malley et al., “Phase 2 Study of ANS-6637, aSpecific Inhibitor of ALDH2, in Treatment Seeking Individuals WithAlcohol Use Disorder: A Combined Human Laboratory and OutpatientClinical Trial,” (2021) Neuropsychopharmacology. Vol. 46: 416-417.

In view of the problematic hepatotoxicity of the ALDH-2 inhibitor,2,6-dichloro-N-[4-(2-oxo-1,2-dihydro-pyridin-4-yl)-benzyl]-benzamide,there remains a need for ALDH-2 inhibitor compounds with no hepatotoxicliability.

SUMMARY

The present disclosure relates generally to compounds that inhibitALDH-2, pharmaceutical compositions comprising these compounds, and usesof these compounds for the treatment of addiction and compulsive eatingdisorder and/or anxiety disorder in mammals. This summary is intended tointroduce the subject matter of the present disclosure, but does notcover each and every embodiment, combination, or variation that iscontemplated and described within the present disclosure. Furtherembodiments are contemplated and described by the disclosure of thedetailed description, drawings, and claims.

In at least one embodiment, the present disclosure provides a compoundof structural Formula

-   -   wherein:        -   X¹ is N or CR³, X² is N or CR⁴, X³ is N or CR⁶, with the            proviso that no more than one of X¹, X², and X³ is N;        -   each of X⁴, and X⁵ is independently N or CR¹⁰;        -   R¹¹ is H, halogen, optionally substituted C₁₋₆ alkyl, or            cycloalkyl;        -   R⁷ is H, or optionally substituted C₁₋₆ alkyl;        -   each of R², R³, R⁴, R⁵, R⁶, R⁸, R⁹, and R¹⁰ is independently            H, halogen, —CF₃, —OH, —CH₂OH, —CN, optionally substituted            alkyl, optionally substituted alkylene, optionally            substituted alkynyl, optionally substituted alkoxy,            optionally substituted cycloalkyl, optionally substituted            aryl, optionally substituted aralkyl, optionally substituted            heteroaryl, optionally substituted heteroaralkyl, optionally            substituted heterocyclyl, aminocarbonyl, acyl, acylamino,            —O—(C₁ to C₆-alkyl)-O—(C₁ to C₆-alkyl),            —CH₂OP(O)(OR²⁰)(OR²¹), —SO₂NR²⁴R²⁵; or —NR²⁴R²⁵, with the            proviso that R² and R⁶ are not both Cl when X¹ is CR³, X² is            CR⁴, X³ is CR⁶, X⁴ is CR¹⁰, X⁵ are CR¹⁰, and R¹¹ is H;        -   each of R²⁰ and R²¹ is independently Na⁺, Li⁺, K⁺, hydrogen,            C₁₋₆ alkyl; or R²⁰ and R²¹ can be combined to represent a            single divalent cation Zn²⁺, Ca²⁺, or Mg²⁺ and each of R²⁴            and R²⁵ is independently chosen from hydrogen or C₁₋₆ alkyl            or when combined together with the nitrogen to which they            are attached form a heterocycle;    -   or a pharmaceutically acceptable salt, ester, single        stereoisomer, mixture of stereoisomers, or a tautomer thereof.

In at least one embodiment of the compound of structure Formula (I),each of R², R³, R⁴, R⁵, R⁷, R⁸, R⁹, R¹⁰, and R¹¹ are H.

In at least one embodiment of the compound of structure Formula (I), X¹is CR³, X² is CR⁴, and X³ is CR⁶. In at least one embodiment of thecompound of structure Formula (I), X¹ is N, X² is CR⁴, and X³ is CR⁶. Inat least one embodiment of the compound of structure Formula (I), X¹ isCR³, X² is N, and X³ is CR⁶. In at least one embodiment of the compoundof structure Formula (I), X¹ is CR³, X² is CR⁴, and X³ is N.

In at least one embodiment of the compound of structure Formula (I), X⁴is CR¹⁰, and X⁵ is CR¹⁰. In at least one embodiment of the compound ofstructure Formula (I), X⁴ is CR¹⁰, and X⁵ is N. In at least oneembodiment of the compound of structure Formula (I), X⁴ is N, and X⁵ isN.

In at least one embodiment of the compound of structure Formula (I), R²is selected from H, Cl, F, or CH₃.

In at least one embodiment of the compound of structure Formula (I), R³is selected from H, Cl, F, and CH₃.

In at least one embodiment of the compound of structure Formula (I), R⁵is selected from H, Cl, F, and CH₃.

In at least one embodiment of the compound of structure Formula (I), R⁶is selected from H, Cl, F, and CF₃.

In at least one embodiment of the compound of structure Formula (I), R¹¹is selected from H and halogen. In at least one embodiment, R¹¹ is a3-fluoro.

In at least one embodiment, the present disclosure provides a compoundof structural Formula (II):

-   -   wherein,        -   each of X² and X³ are independently N or CH;        -   R¹¹ is H, halogen, optionally substituted C₁₋₆ alkyl, or            cycloalkyl;        -   R¹ is selected from

-   -   -   each of R², and R⁶, is independently H, Br, Cl, F, CH₃, or            CF₃; and        -   each of R³, R⁴, and R⁵, is independently H, Br, Cl, F, CH₃,            CF₃, —OH, —CH₂OH, —CN, optionally substituted alkyl,            optionally substituted alkylene, optionally substituted            alkynyl, optionally substituted alkoxy, optionally            substituted cycloalkyl, optionally substituted aryl,            optionally substituted aralkyl, optionally substituted            heteroaryl, optionally substituted heteroaralkyl, optionally            substituted heterocyclyl, aminocarbonyl, acyl, acylamino,            —O—(C₁ to C₆-alkyl)-O—(C₁ to C₆-alkyl),            —CH₂OP(O)(OR²⁰)(OR²¹), —SO₂NR²⁴R²⁵; or —NR²⁴R²⁵, with the            proviso that R² and R⁶ are not both Cl when when R¹ is an            aromatic ring, X² and X³ are CH, and R¹¹ is H;

    -   or a pharmaceutically acceptable salt, ester, single        stereoisomer, mixture of stereoisomers, or a tautomer thereof.

In at least one embodiment of the compound of structure Formula (II), X²and X³ are CH.

In at least one embodiment of the compound of structure Formula (II), X²is CH and X³ is N.

In at least one embodiment of the compound of structure Formula (II),R¹¹ is H. In at least one embodiment, R¹¹ is 3-fluoro.

In at least one embodiment of the compound of structure Formula (II),R³, R⁴, and R⁵ are H. In at least one embodiment, R³, R⁴, and R⁵ areindependently H, Cl, F, CH₃, or CF₃.

In at least one embodiment of the compound of structure Formula (II), R²is H, Cl, F, or CH₃.

In at least one embodiment of the compound of structure Formula (II), R⁶is H, Br, Cl, F, or CF₃.

In at least one embodiment of the compound of structure Formula (II), R¹is selected from:

In at least one embodiment, the compound of structural Formula (I) orstructural Formula (II) of the present disclosure is selected fromcompounds (1a), (1b), (1c), (1d), (1e), (1f), (1g), (1h), (1i), (1j),(1k), (1l), (1m), and (1n), the structures of which are depicted belowin Table 1, including pharmaceutically acceptable salts, esters, singlestereoisomers, mixtures of stereoisomers, or tautomers thereof.

TABLE 1 Exemplary ALDH-2 Inhibitor Compounds

In at least one embodiment, the present disclosure provides apharmaceutical composition comprising a therapeutically effective amountof the compound of structural Formula (I) or Formula (II), or apharmaceutically acceptable salt, ester, single stereoisomer, mixture ofstereoisomers, or a tautomer thereof, and a pharmaceutically acceptablecarrier.

In at least one embodiment, the present disclosure provides a method oftreating chemical dependency on a substance or condition of addiction orabuse comprising administering a compound of structural Formula (I) orFormula (II) (e.g., a compound of Table 1) or a pharmaceuticallyacceptable salt, ester, single stereoisomer, mixture of stereoisomers,or a tautomer thereof, or administering a pharmaceutical compositioncomprising a therapeutically effective amount of the compound ofstructural Formula (I) or Formula (II), or a pharmaceutically acceptablesalt, ester, single stereoisomer, mixture of stereoisomers, or atautomer thereof. In at least one embodiment, substance or condition ofaddiction or abuse is selected from the group consisting of alcohol,nicotine, cocaine, opiates, amphetamines, and compulsive eating.

In at least one embodiment, the present disclosure provides a method oftreating compulsive eating comprising administering to a human patient acompound of structural Formula (I) or Formula (II) or administering apharmaceutical composition comprising a therapeutically effective amountof the compound of structural Formula (I) or Formula (II), or apharmaceutically acceptable salt, ester, single stereoisomer, mixture ofstereoisomers, or a tautomer thereof.

In at least one embodiment, the present disclosure provides a method oftreating a compulsive eating disorder comprising administering to ahuman patient a compound of structural Formula (I) or Formula (II), or apharmaceutically acceptable salt, ester, single stereoisomer, mixture ofstereoisomers, or a tautomer thereof, or administering a pharmaceuticalcomposition comprising a therapeutically effective amount of thecompound of structural Formula (I) or Formula (II), or apharmaceutically acceptable salt, ester, single stereoisomer, mixture ofstereoisomers, or a tautomer thereof. In at least one embodiment, thepresent disclosure provides a method of treating anxiety comprisingadministering to a human patient a compound of structural Formula (I) orFormula (II), or a pharmaceutically acceptable salt, ester, singlestereoisomer, mixture of stereoisomers, or a tautomer thereof, oradministering a pharmaceutical composition comprising a therapeuticallyeffective amount of the compound of structural Formula (I) or Formula(II), or a pharmaceutically acceptable salt, ester, single stereoisomer,mixture of stereoisomers, or a tautomer thereof.

In at least one embodiment, the present disclosure provides an ALDH-2inhibitor comprising a compound of structural Formula (I) or Formula(II), or a pharmaceutically acceptable salt, ester, single stereoisomer,mixture of stereoisomers, or a tautomer thereof, for use in therapy, foruse as a medicament, for use in treating chemical dependency on asubstance, for use in treating a condition of addiction or abuse, foruse in treating a compulsive eating disorder, or for use in treating ananxiety disorder.

In at least one embodiment, the present disclosure provides an ALDH-2inhibitor comprising a compound of structural Formula (I) or Formula(II), or a pharmaceutically acceptable salt, ester, single stereoisomer,mixture of stereoisomers, or a tautomer thereof, for use in themanufacture of a pharmaceutical composition or a medicament for thetreatment of chemical dependency on a substance, for use in treating acondition of addiction or abuse, for use in treating a compulsive eatingdisorder, or for use in treating an anxiety disorder.

DETAILED DESCRIPTION

It is to be understood that the detailed descriptions provided herein,including the drawings, are exemplary and explanatory only and are notrestrictive of this disclosure. The description is not limited to thespecific compounds, compositions, methods, techniques, protocols, celllines, assays, and reagents disclosed herein, as these may vary, but isalso intended to encompass known variants of these specific embodiments.

It is also to be understood that the terminology used herein is intendedto describe particular embodiments and is in not intended to limit thescope as set forth in the appended claims. For the descriptions hereinand the appended claims, the singular forms “a”, and “an” include pluralreferents unless the context clearly indicates otherwise. Thus, forexample, reference to “a protein” includes more than one protein, andreference to “a compound” refers to more than one compound. The use of“comprise,” “comprises,” “comprising” “include,” “includes,” and“including” are interchangeable and not intended to be limiting. It isto be further understood that where descriptions of various embodimentsuse the term “comprising,” those skilled in the art would understandthat in some specific instances, an embodiment can be alternativelydescribed using language “consisting essentially of” or “consisting of.”

Further, it is understood that where a range of values is provided,unless the context clearly dictates otherwise, it is understood thateach intervening integer of the value, and each tenth of eachintervening integer of the value, unless the context clearly dictatesotherwise, between the upper and lower limit of that range, and anyother stated or intervening value in that stated range, is encompassedwithin the invention. The upper and lower limits of these smaller rangesmay independently be included in the smaller ranges, and are alsoencompassed within the invention, subject to any specifically excludedlimit in the stated range. Where the stated range includes one or bothof the limits, ranges excluding (i) either or (ii) both of thoseincluded limits are also included in the invention. For example, “1 to50” includes “2 to 25”, “5 to 20”, “25 to 50”, “1 to 10”, etc.

Abbreviations, Definitions and General Parameters

As used in the present specification, the following words and phrasesare generally intended to have the meanings as set forth below, exceptto the extent that the context in which they are used indicatesotherwise.

The term “ALDH-2 inhibitor” as used herein includes any compound thatselectively inhibits the enzyme aldehyde dehydrogenase 2. ExemplaryALDH-2 inhibitor compounds include the isoflavone compound, daidzein(see e.g., U.S. Pat. Nos. 5,624,910, and 6,121,010), and itsstructurally related isoflavone derivative compounds (see e.g., U.S.Pat. Nos. 7,951,813, 8,158,810, and 8,673,966; Int'l Pat. Publ. Nos.WO2008/014497, WO2008/124532, WO2009/061924, WO2009/094028, andWO2013/033377), and compounds of Formula (I), which are structurallyunrelated to the isoflavones, such as2,6-dichloro-N-[4-(2-oxo-1,2-dihydro-pyridin-4-yl)-benzyl]-benzamide(see e.g., U.S. Pat. Nos. 8,558,001, 8,575,353, 9,000,015, 9,610,299;Int'l Pat. Publ. WO2013/006400).

The term “addiction” as used herein includes any substance use disorderincluding, but not limited to, substance misuse, substance dependence,substance addiction, and/or condition of addiction, such as a compulsiveor binge eating disorder, and/or an anxiety disorder, each individuallyor concurrent. Exemplary substances of misuse, dependence, and/oraddiction, include but are not limited to, alcohol, nicotine, cocaine,opiates, and amphetamines.

The term “alcohol” as used herein in the context of dopamine producingagents that may be consumed by humans refers to ethanol (“EtOH”).

The term “anxiety disorder” as used herein refers to anxiety that doesnot go away, gets worse over time, and which results in symptoms thatcan interfere with daily activities such as job performance, schoolwork,and relationships. Exemplary anxiety disorders include but are notlimited to generalized anxiety disorder, panic disorder, social anxietydisorder, and various phobia-related disorders.

The term “compulsive eating disorder” or “binge eating disorder” as usedherein refers to a disorder characterized by recurrent binge eatingepisodes during which a person feels a loss of control and markeddistress over his or her eating, and results in the person becomingoverweight or obese.

The term “therapeutically effective amount” refers to an amount that issufficient to effect treatment, as defined below, when administered to amammal in need of such treatment. The therapeutically effective amountwill vary depending upon the subject and disease condition beingtreated, the weight and age of the subject, the severity of the diseasecondition, the manner of administration and the like, which can readilybe determined by one of ordinary skill in the art.

The term “unit dosage form” refers to physically discrete units suitableas unitary dosages for human subjects and other mammals, each unitcontaining a predetermined quantity of active ingredient that producesthe desired therapeutic effect, in association with a suitablepharmaceutical excipient (e.g., a tablet, capsule, or ampoule).

The term “active ingredient” refers to a compound in a pharmaceuticalcomposition that has a pharmacological effect when administered to anorganism (e.g., a mammal) and is intended to encompass not only thecompound but also the pharmaceutically acceptable salts,pharmaceutically acceptable esters, hydrates, polymorphs, and prodrugsof such compound.

The term “prodrug” refers to a compound that includes a chemical groupwhich, in vivo, can be converted and/or split off from the remainder ofthe molecule to provide for the active drug, a pharmaceuticallyacceptable salt thereof, or a biologically active metabolite thereof.

The term “treatment” or “treating” means any administration of acompound of the disclosure to a mammal having a disease or disorder, ora mammal susceptible to a disease or disorder, for purposes including:

-   -   (i) preventing the disease, that is, causing the clinical        symptoms of the disease not to develop;    -   (ii) inhibiting the disease, that is, arresting the development        of clinical symptoms; and/or    -   (iii) relieving the disease, i.e., causing the regression of        clinical symptoms.

The term “during treatment” as used herein refers to the time periodafter administration of a therapeutically effective amount of a compoundto a subject for treatment of a disease or disorder until the time atwhich the amount of the compound in the subject has decreased to a levelbelow what is therapeutically effective.

The term “alkyl” refers to a monoradical branched or unbranchedsaturated hydrocarbon chain having from 1 to 20 carbon atoms. This termis exemplified by groups such as methyl, ethyl, n-propyl, iso-propyl,n-butyl, iso-butyl, t-butyl, n-hexyl, n-decyl, tetradecyl, and the like.

The term “substituted alkyl” refers to:

-   -   (i) an alkyl group as defined above, having 1, 2, 3, 4 or 5        substituents, (typically 1, 2, or 3 substituents) selected from        the group consisting of alkenyl, alkynyl, alkoxy, cycloalkyl,        cycloalkenyl, acyl, acylamino, acyloxy, amino, aminocarbonyl,        alkoxycarbonylamino, azido, cyano, halogen, hydroxy, keto,        thiocarbonyl, carboxy, carboxyalkyl, arylthio, heteroarylthio,        heterocyclylthio, thiol, alkylthio, aryl, aryloxy, heteroaryl,        aminosulfonyl, aminocarbonylamino, heteroaryloxy, heterocyclyl,        heterocyclyloxy, hydroxyamino, alkoxyamino, nitro, —SO-alkyl,        —SO-aryl, —SO-heteroaryl, —SO₂-alkyl, SO₂-aryl and        —SO₂-heteroaryl. Unless otherwise constrained by the definition,        all substituents may optionally be further substituted by 1, 2,        or 3 substituents chosen from alkyl, carboxy, carboxyalkyl,        aminocarbonyl, hydroxy, alkoxy, halogen, CF₃, amino, substituted        amino, cyano, and —S(O)_(n)R, where R is alkyl, aryl, or        heteroaryl and n is 0, 1 or 2; or    -   (ii) an alkyl group as defined above that is interrupted by 1-10        atoms (e.g. 1, 2, 3, 4, or 5 atoms) independently chosen from        oxygen, sulfur and NR^(a), where R^(a) is chosen from hydrogen,        alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, aryl,        heteroaryl and heterocyclyl. All substituents may be optionally        further substituted by alkyl, alkoxy, halogen, CF₃, amino,        substituted amino, cyano, or —S(O)_(n)R, in which R is alkyl,        aryl, or heteroaryl and n is 0, 1 or 2; or    -   (iii) an alkyl group as defined above that has both 1, 2, 3, 4        or 5 substituents as defined above and is also interrupted by        1-10 atoms (e.g. 1, 2, 3, 4, or 5 atoms) as defined above.

The term “lower alkyl” refers to a monoradical branched or unbranchedsaturated hydrocarbon chain having 1, 2, 3, 4, 5, or 6 carbon atoms.This term is exemplified by groups such as methyl, ethyl, n-propyl,iso-propyl, n-butyl, iso-butyl, t-butyl, n-hexyl, and the like.

The term “substituted lower alkyl” refers to lower alkyl as definedabove having 1 to 5 substituents (typically 1, 2, or 3 substituents), asdefined for substituted alkyl, or a lower alkyl group as defined abovethat is interrupted by 1, 2, 3, 4, or 5 atoms as defined for substitutedalkyl, or a lower alkyl group as defined above that has both 1, 2, 3, 4or 5 substituents as defined above and is also interrupted by 1, 2, 3,4, or 5 atoms as defined above.

The term “alkylene” refers to a diradical of a branched or unbranchedsaturated hydrocarbon chain, typically having from 1 to 20 carbon atoms(e.g. 1-10 carbon atoms, or 1, 2, 3, 4, 5 or 6 carbon atoms). This termis exemplified by groups such as methylene (—CH₂—), ethylene (—CH₂CH₂—),the propylene isomers (e.g., —CH₂CH₂CH₂— and —CH(CH₃)CH₂—), and thelike.

The term “lower alkylene” refers to a diradical of a branched orunbranched saturated hydrocarbon chain, typically having 1, 2, 3, 4, 5,or 6 carbon atoms.

The term “substituted alkylene” refers to:

-   -   (i) an alkylene group as defined above having 1, 2, 3, 4, or 5        substituents (typically 1, 2, or 3 substituents) selected from        the group consisting of alkyl, alkenyl, alkynyl, alkoxy,        cycloalkyl, cycloalkenyl, acyl, acylamino, acyloxy, amino,        aminocarbonyl, alkoxycarbonylamino, azido, cyano, halogen,        hydroxy, keto, thiocarbonyl, carboxy, carboxyalkyl, arylthio,        heteroarylthio, heterocyclylthio, thiol, alkylthio, aryl,        aryloxy, heteroaryl, aminosulfonyl, aminocarbonylamino,        heteroaryloxy, heterocyclyl, heterocyclyloxy, hydroxyamino,        alkoxyamino, nitro, —SO-alkyl, —SO-aryl, —SO-heteroaryl,        —SO₂-alkyl, SO₂-aryl and —SO₂-heteroaryl. Unless otherwise        constrained by the definition, all substituents may optionally        be further substituted by 1, 2, or 3 substituents chosen from        alkyl, carboxy, carboxyalkyl, aminocarbonyl, hydroxy, alkoxy,        halogen, CF₃, amino, substituted amino, cyano, and —S(O)_(n)R,        where R is alkyl, aryl, or heteroaryl and n is 0, 1 or 2; or    -   (ii) an alkylene group as defined above that is interrupted by        1-10 groups (e.g. 1, 2, 3, 4, or 5 groups) independently chosen        from —O—, —S—, sulfonyl, —C(O)—, —C(O)O—, —C(O)N—, and —NR^(a),        where R^(a) is chosen from hydrogen, optionally substituted        alkyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl and        heterocyclyl; or    -   (iii) an alkylene group as defined above that has both 1, 2, 3,        4 or 5 substituents as defined above and is also interrupted by        1-10 groups as defined above. Examples of substituted alkylenes        are chloromethylene (—CH(Cl)—), aminoethylene (—CH(NH₂)CH₂—),        methylaminoethylene (—CH(NHMe)CH₂—), 2-carboxypropylene isomers        (—CH₂CH(CO₂H)CH₂—), ethoxyethyl (—CH₂CH₂O—CH₂CH₂—),        ethylmethylaminoethyl (—CH₂CH₂—N(CH₃)—CH₂CH₂—),        1-ethoxy-2-(2-ethoxy-ethoxy)ethane        (—CH₂CH₂O—CH₂CH₂—OCH₂CH₂—OCH₂CH₂—), and the like.

The term “aralkyl” refers to an aryl group covalently linked to analkylene group, where aryl and alkylene are defined herein. “Optionallysubstituted aralkyl” refers to an optionally substituted aryl groupcovalently linked to an optionally substituted alkylene group. Sucharalkyl groups are exemplified by benzyl, phenylethyl,3-(4-methoxyphenyl)propyl, and the like.

The term “aralkyloxy” refers to the group —O-aralkyl. “Optionallysubstituted aralkyloxy” refers to an optionally substituted aralkylgroup covalently linked to an optionally substituted alkylene group.Such aralkyl groups are exemplified by benzyloxy, phenylethyloxy, andthe like.

The term “alkoxy” refers to the group R—O—, where R is optionallysubstituted alkyl or optionally substituted cycloalkyl, or R is a group—Y—Z, in which Y is optionally substituted alkylene and Z is optionallysubstituted alkenyl, optionally substituted alkynyl; or optionallysubstituted cycloalkenyl, where alkyl, alkenyl, alkynyl, cycloalkyl andcycloalkenyl are as defined herein. Typical alkoxy groups are alkyl-O—and include, by way of example, methoxy, ethoxy, n-propoxy, iso-propoxy,n-butoxy, tert-butoxy, sec-butoxy, n-pentoxy, n-hexyloxy,1,2-dimethylbutoxy, and the like.

The term “lower alkoxy” refers to the group R—O— in which R isoptionally substituted lower alkyl as defined above. This term isexemplified by groups such as methoxy, ethoxy, n-propoxy, iso-propoxy,n-butoxy, iso-butoxy, t-butoxy, n-hexyloxy, and the like.

The term “alkylthio” refers to the group R—S—, where R is as defined foralkoxy.

The term “alkenyl” refers to a monoradical of a branched or unbranchedunsaturated hydrocarbon group typically having from 2 to 20 carbon atoms(more typically from 2 to 10 carbon atoms, e.g. 2 to 6 carbon atoms) andhaving from 1 to 6 carbon-carbon double bonds, e.g. 1, 2, or 3carbon-carbon double bonds. Typical alkenyl groups include ethenyl (orvinyl, i.e. —CH═CH₂), 1-propylene (or allyl, —CH₂CH═CH₂), isopropylene(—C(CH₃)═CH₂), bicyclo[2.2.1]heptene, and the like. In the event thatalkenyl is attached to nitrogen, the double bond cannot be alpha to thenitrogen.

The term “lower alkenyl” refers to alkenyl as defined above having from2 to 6 carbon atoms.

The term “substituted alkenyl” refers to an alkenyl group as definedabove having 1, 2, 3, 4 or 5 substituents (typically 1, 2, or 3substituents), selected from the group consisting of alkyl, alkenyl,alkynyl, alkoxy, cycloalkyl, cycloalkenyl, acyl, acylamino, acyloxy,amino, aminocarbonyl, alkoxycarbonylamino, azido, cyano, halogen,hydroxy, keto, thiocarbonyl, carboxy, carboxyalkyl, arylthio,heteroarylthio, heterocyclylthio, thiol, alkylthio, aryl, aryloxy,heteroaryl, aminosulfonyl, aminocarbonylamino, heteroaryloxy,heterocyclyl, heterocyclooxy, hydroxyamino, alkoxyamino, nitro,—SO-alkyl, —SO-aryl, —SO-heteroaryl, —SO₂-alkyl, SO₂-aryl and—SO₂-heteroaryl. Unless otherwise constrained by the definition, allsubstituents may optionally be further substituted by 1, 2, or 3substituents chosen from alkyl, carboxy, carboxyalkyl, aminocarbonyl,hydroxy, alkoxy, halogen, CF₃, amino, substituted amino, cyano, and—S(O)_(n)R, where R is alkyl, aryl, or heteroaryl and n is 0, 1 or 2.

The term “alkynyl” refers to a monoradical of an unsaturatedhydrocarbon, typically having from 2 to 20 carbon atoms (more typicallyfrom 2 to 10 carbon atoms, e.g. 2 to 6 carbon atoms) and having from 1to 6 carbon-carbon triple bonds e.g. 1, 2, or 3 carbon-carbon triplebonds. Typical alkynyl groups include ethynyl (—C≡CH), propargyl (orpropynyl, —C≡CCH₃), and the like. In the event alkynyl is attached tonitrogen, the triple bond cannot be alpha to the nitrogen.

The term “substituted alkynyl” refers to an alkynyl group as definedabove having 1, 2, 3, 4 or 5 substituents (typically 1, 2, or 3substituents), selected from the group consisting of alkyl, alkenyl,alkynyl, alkoxy, cycloalkyl, cycloalkenyl, acyl, acylamino, acyloxy,amino, aminocarbonyl, alkoxycarbonylamino, azido, cyano, halogen,hydroxy, keto, thiocarbonyl, carboxy, carboxyalkyl, arylthio,heteroarylthio, heterocyclylthio, thiol, alkylthio, aryl, aryloxy,heteroaryl, aminosulfonyl, aminocarbonylamino, heteroaryloxy,heterocyclyl, heterocyclyloxy, hydroxyamino, alkoxyamino, nitro,—SO-alkyl, —SO-aryl, —SO-heteroaryl, —SO₂-alkyl, SO₂-aryl and—SO₂-heteroaryl. Unless otherwise constrained by the definition, allsubstituents may optionally be further substituted by 1, 2, or 3substituents chosen from alkyl, carboxy, carboxyalkyl, aminocarbonyl,hydroxy, alkoxy, halogen, CF₃, amino, substituted amino, cyano, and—S(O)_(n)R, where R is alkyl, aryl, or heteroaryl and n is 0, 1 or 2.

The term “aminocarbonyl” refers to the group —C(O)NRR where each R isindependently hydrogen, alkyl, cycloalkyl, aryl, heteroaryl,heterocyclyl or where both R groups are joined to form a heterocyclicgroup (e.g., morpholino). Unless otherwise constrained by thedefinition, all substituents may optionally be further substituted by 1,2, or 3 substituents chosen from alkyl, carboxy, carboxyalkyl,aminocarbonyl, hydroxy, alkoxy, halogen, CF₃, amino, substituted amino,cyano, and —S(O)_(n)R, where R is alkyl, aryl, or heteroaryl and n is 0,1 or 2.

The term “ester” or “carboxyester” refers to the group —C(O)OR, where Ris alkyl, cycloalkyl, aryl, heteroaryl, or heterocyclyl, which may beoptionally further substituted by alkyl, alkoxy, halogen, CF₃, amino,substituted amino, cyano, or —S(O)_(n)R^(a), in which R^(a) is alkyl,aryl, or heteroaryl and n is 0, 1 or 2.

The term “acylamino” refers to the group —NRC(O)R where each R isindependently hydrogen, alkyl, aryl, heteroaryl, or heterocyclyl. Allsubstituents may be optionally further substituted by alkyl, alkoxy,halogen, CF₃, amino, substituted amino, cyano, or —S(O)_(n)R, in which Ris alkyl, aryl, or heteroaryl and n is 0, 1 or 2.

The term “acyloxy” refers to the groups —OC(O)-alkyl, —OC(O)-cycloalkyl,—OC(O)-aryl, —OC(O)-heteroaryl, and —OC(O)-heterocyclyl. Unlessotherwise constrained by the definition, all substituents may optionallybe further substituted by 1, 2, or 3 substituents chosen from alkyl,carboxy, carboxyalkyl, aminocarbonyl, hydroxy, alkoxy, halogen, CF₃,amino, substituted amino, cyano, and —S(O)_(n)R, where R is alkyl, aryl,or heteroaryl and n is 0, 1 or 2.

The term “aryl” refers to an aromatic carbocyclic group of 6 to 20carbon atoms having a single ring (e.g., phenyl) or multiple rings(e.g., biphenyl), or multiple condensed (fused) rings (e.g., naphthyl,fluorenyl, and anthryl). Typical aryls include phenyl, fluorenyl,naphthyl, anthryl, and the like.

Unless otherwise constrained by the definition for the aryl substituent,such aryl groups can optionally be substituted with 1, 2, 3, 4 or 5substituents (typically 1, 2, or 3 substituents), selected from thegroup consisting of alkyl, alkenyl, alkynyl, alkoxy, cycloalkyl,cycloalkenyl, acyl, acylamino, acyloxy, amino, aminocarbonyl,alkoxycarbonylamino, azido, cyano, halogen, hydroxy, keto, thiocarbonyl,carboxy, carboxyalkyl, arylthio, heteroarylthio, heterocyclylthio,thiol, alkylthio, aryl, aryloxy, heteroaryl, aminosulfonyl,aminocarbonylamino, heteroaryloxy, heterocyclyl, heterocyclyloxy,hydroxyamino, alkoxyamino, nitro, —SO-alkyl, —SO-aryl, —SO-heteroaryl,—SO₂-alkyl, SO₂-aryl and —SO₂-heteroaryl. Unless otherwise constrainedby the definition, all substituents may optionally be furthersubstituted by 1, 2, or 3 substituents chosen from alkyl, carboxy,carboxyalkyl, aminocarbonyl, hydroxy, alkoxy, halogen, CF₃, amino,substituted amino, cyano, and —S(O)_(n)R, where R is alkyl, aryl, orheteroaryl and n is 0, 1 or 2.

The term “aryloxy” refers to the group aryl-O— wherein the aryl group isas defined above and includes optionally substituted aryl groups as alsodefined above. The term “arylthio” refers to the group R—S—, where R isas defined for aryl.

The term “amino” refers to the group —NH₂.

The term “substituted amino” refers to the group —NRR where each R isindependently selected from the group consisting of hydrogen, alkyl,cycloalkyl, aryl, heteroaryl and heterocyclyl provided that both Rgroups are not hydrogen, or a group —Y—Z, in which Y is optionallysubstituted alkylene and Z is alkenyl, cycloalkenyl, or alkynyl. Unlessotherwise constrained by the definition, all substituents may optionallybe further substituted by 1, 2, or 3 substituents chosen from alkyl,carboxy, carboxyalkyl, aminocarbonyl, hydroxy, alkoxy, halogen, CF₃,amino, substituted amino, cyano, and —S(O)_(n)R, where R is alkyl, aryl,or heteroaryl and n is 0, 1 or 2.

The term “carboxyalkyl” refers to the groups —C(O)O-alkyl,—C(O)O-cycloalkyl, where alkyl and cycloalkyl are as defined herein, andmay be optionally further substituted by alkyl, alkenyl, alkynyl,alkoxy, halogen, CF₃, amino, substituted amino, cyano, or —S(O)_(n)R, inwhich R is alkyl, aryl, or heteroaryl and n is 0, 1 or 2.

The term “cycloalkyl” refers to cyclic alkyl groups of from 3 to 20carbon atoms having a single cyclic ring or multiple condensed rings.Such cycloalkyl groups include, by way of example, single ringstructures such as cyclopropyl, cyclobutyl, cyclopentyl, cyclooctyl, andthe like, or multiple ring structures such as adamantanyl, andbicyclo[2.2.1]heptane, or cyclic alkyl groups to which is fused an arylgroup, for example indan, and the like.

The term “cycloalkenyl” refers to cyclic alkyl groups of from 3 to 20carbon atoms having a single cyclic ring or multiple condensed rings andhaving at least one double bond and preferably from 1 to 2 double bonds.

The terms “substituted cycloalkyl” and “substituted cycloalkenyl” referto cycloalkyl or cycloalkenyl groups having 1, 2, 3, 4 or 5 substituents(typically 1, 2, or 3 substituents), selected from the group consistingof alkyl, alkenyl, alkynyl, alkoxy, cycloalkyl, cycloalkenyl, acyl,acylamino, acyloxy, amino, aminocarbonyl, alkoxycarbonylamino, azido,cyano, halogen, hydroxy, keto, thiocarbonyl, carboxy, carboxyalkyl,arylthio, heteroarylthio, heterocyclylthio, thiol, alkylthio, aryl,aryloxy, heteroaryl, aminosulfonyl, aminocarbonylamino, heteroaryloxy,heterocyclyl, heterocyclyloxy, hydroxyamino, alkoxyamino, nitro,—SO-alkyl, —SO-aryl, —SO-heteroaryl, —SO₂-alkyl, SO₂-aryl and—SO₂-heteroaryl. The term “substituted cycloalkyl” also includescycloalkyl groups wherein one or more of the annular carbon atoms of thecycloalkyl group is a carbonyl group (i.e. an oxygen atom is oxo to thering). Unless otherwise constrained by the definition, all substituentsmay optionally be further substituted by 1, 2, or 3 substituents chosenfrom alkyl, carboxy, carboxyalkyl, aminocarbonyl, hydroxy, alkoxy,halogen, CF₃, amino, substituted amino, cyano, and —S(O)_(n)R, where Ris alkyl, aryl, or heteroaryl and n is 0, 1 or 2.

The term “halogen” or “halo” refers to fluoro, bromo, chloro, and iodo.

The term “acyl” denotes a group —C(O)R, in which R is hydrogen,optionally substituted alkyl, optionally substituted cycloalkyl,optionally substituted heterocyclyl, optionally substituted aryl, andoptionally substituted heteroaryl.

The term “alkoxycarbonylamino” refers to a group —NHC(O)OR in which R isoptionally substituted alkyl.

The term “alkyl amine” refers to R—NH₂ in which R is optionallysubstituted alkyl.

The term “dialkyl amine” refers to R—NHR in which each R isindependently an optionally substituted alkyl.

The term “trialkyl amine” refers to NR₃ in which R each R isindependently an optionally substituted alkyl.

The term “azido” refers to a group

The term “hydroxyl” or “hydroxyl” refers to a group —OH.

The term “arylthio” refers to the group —S-aryl.

The term “heterocyclylthio” refers to the group —S-heterocyclyl.

The term “alkylthio” refers to the group —S-alkyl.

The term “aminosulfonyl” refers to the group —SO₂NRR, wherein each R isindependently selected from the group consisting of hydrogen, alkyl,cycloalkyl, aryl, heteroaryl and heterocyclyl. Unless otherwiseconstrained by the definition, all substituents may optionally befurther substituted by 1, 2, or 3 substituents selected from the groupconsisting of alkyl, alkenyl, alkynyl, alkoxy, cycloalkyl, cycloalkenyl,acyl, acylamino, acyloxy, amino, aminocarbonyl, alkoxycarbonylamino,azido, cyano, halogen, hydroxy, keto, thiocarbonyl, carboxy,carboxyalkyl, arylthio, heteroarylthio, heterocyclylthio, thiol,alkylthio, aryl, aryloxy, heteroaryl, aminosulfonyl, aminocarbonylamino,heteroaryloxy, heterocyclyl, heterocyclyloxy, hydroxyamino, alkoxyamino,nitro, —SO-alkyl, —SO-aryl, —SO-heteroaryl, —SO₂-alkyl, SO₂-aryl and—SO₂-heteroaryl.

The term “aminocarbonylamino” refers to the group —NR^(c)C(O)NRR,wherein R^(c) is hydrogen or alkyl and each R is independently selectedfrom the group consisting of hydrogen, alkyl, cycloalkyl, aryl,heteroaryl and heterocyclyl. Unless otherwise constrained by thedefinition, all substituents may optionally be further substituted by 1,2, or 3 substituents selected from the group consisting of alkyl,alkenyl, alkynyl, alkoxy, cycloalkyl, cycloalkenyl, acyl, acylamino,acyloxy, amino, aminocarbonyl, alkoxycarbonylamino, azido, cyano,halogen, hydroxy, keto, thiocarbonyl, carboxy, carboxyalkyl, arylthio,heteroarylthio, heterocyclylthio, thiol, alkylthio, aryl, aryloxy,heteroaryl, aminosulfonyl, aminocarbonylamino, heteroaryloxy,heterocyclyl, heterocyclooxy, hydroxyamino, alkoxyamino, nitro,—SO-alkyl, —SO-aryl, —SO-heteroaryl, —SO₂-alkyl, SO₂-aryl and—SO₂-heteroaryl.

The term “heterocyclooxy” refers to the group —O-heterocyclyl.

The term “alkoxyamino” refers to the group —NHOR in which R isoptionally substituted alkyl.

The term “hydroxyamino” refers to the group —NHOH.

The term “heteroaryl” refers to a group comprising single or multiplerings comprising 1 to 15 carbon atoms and 1 to 4 heteroatoms selectedfrom oxygen, nitrogen, and sulfur within at least one ring. The term“heteroaryl” is generic to the terms “aromatic heteroaryl” and“partially saturated heteroaryl.” The term “aromatic heteroaryl” refersto a heteroaryl in which at least one ring is aromatic. Examples ofaromatic heteroaryls include pyrrole, thiophene, pyridine, quinoline,pteridine. The term “partially saturated heteroaryl” refers to aheteroaryl having a structure equivalent to an underlying aromaticheteroaryl which has had one or more double bonds in an aromatic ring ofthe underlying aromatic heteroaryl saturated. Examples of partiallysaturated heteroaryls include dihydropyrrole, dihydropyridine, chroman,and the like.

Unless otherwise constrained by the definition for the heteroarylsubstituent, such heteroaryl groups can be optionally substituted with 1to 5 substituents (typically 1, 2, or 3 substituents) selected from thegroup consisting of alkyl, alkenyl, alkynyl, alkoxy, cycloalkyl,cycloalkenyl, acyl, acylamino, acyloxy, amino, aminocarbonyl,alkoxycarbonylamino, azido, cyano, halogen, hydroxy, keto, thiocarbonyl,carboxy, carboxyalkyl (an alkyl ester), arylthio, heteroaryl,heteroarylthio, heterocyclylthio, thiol, alkylthio, aryl, aryloxy,aralkyl, heteroaryl, aminosulfonyl, aminocarbonylamino, heteroaryloxy,heterocyclyl, heterocyclooxy, hydroxyamino, alkoxyamino, nitro,—SO-alkyl, —SO-aryl, —SO-heteroaryl, —SO₂-alkyl, SO₂-aryl and—SO₂-heteroaryl. Unless otherwise constrained by the definition, allsubstituents may optionally be further substituted by 1, 2, or 3substituents chosen from alkyl, carboxy, carboxyalkyl, aminocarbonyl,hydroxy, alkoxy, halogen, CF₃, amino, substituted amino, cyano, and—S(O)_(n)R, where R is alkyl, aryl, or heteroaryl and n is 0, 1 or 2.Such heteroaryl groups can have a single ring (e.g., pyridyl or furyl)or multiple condensed rings (e.g., indolizinyl, benzothiazole, orbenzothienyl). Examples of nitrogen heterocyclyls and heteroarylsinclude, but are not limited to, pyrrole, imidazole, pyrazole, pyridine,pyrazine, pyrimidine, pyridazine, indolizine, isoindole, indole,indazole, purine, quinolizine, isoquinoline, quinoline, phthalazine,naphthylpyridine, quinoxaline, quinazoline, cinnoline, pteridine,carbazole, carboline, phenanthridine, acridine, phenanthroline,isothiazole, phenazine, isoxazole, phenoxazine, phenothiazine,imidazolidine, imidazoline, and the like as well as N-alkoxy-nitrogencontaining heteroaryl compounds.

The term “heteroaryloxy” refers to the group heteroaryl-O—.

The term “heterocyclyl,” “heterocycle,” or “heterocyclic” refers to amonoradical saturated group having a single ring or multiple condensedrings, having from 1 to 40 carbon atoms and from 1 to 10 hetero atoms,preferably 1 to 4 heteroatoms, selected from nitrogen, sulfur,phosphorus, and/or oxygen within the ring.

Unless otherwise constrained by the definition for the heterocyclicsubstituent, such heterocyclic groups can be optionally substituted with1 to 5 substituents (typically 1, 2, or 3 substituents), selected fromthe group consisting of alkyl, alkenyl, alkynyl, alkoxy, cycloalkyl,cycloalkenyl, acyl, acylamino, acyloxy, amino, aminocarbonyl,alkoxycarbonylamino, azido, cyano, halogen, hydroxy, keto, thiocarbonyl,carboxy, carboxyalkyl, arylthio, heteroarylthio, heterocyclylthio,thiol, alkylthio, aryl, aryloxy, heteroaryl, aminosulfonyl,aminocarbonylamino, heteroaryloxy, heterocyclyl, heterocyclooxy,hydroxyamino, alkoxyamino, nitro, —SO-alkyl, —SO-aryl, —SO-heteroaryl,—SO₂-alkyl, SO₂-aryl and —SO₂-heteroaryl. Unless otherwise constrainedby the definition, all substituents may optionally be furthersubstituted by 1, 2, or 3 substituents chosen from alkyl, carboxy,carboxyalkyl, aminocarbonyl, hydroxy, alkoxy, halogen, CF₃, amino,substituted amino, cyano, and —S(O)_(n)R, where R is alkyl, aryl, orheteroaryl and n is 0, 1 or 2. Preferred heterocyclics includetetrahydrofuranyl, morpholino, piperidinyl, and the like.

The term “thiol” refers to the group —SH.

The term “substituted alkylthio” refers to the group —S-substitutedalkyl.

The term “heteroarylthiol” refers to the group —S-heteroaryl wherein theheteroaryl group is as defined above including optionally substitutedheteroaryl groups as also defined above.

The term “sulfoxide” refers to a group —S(O)R, in which R is alkyl,aryl, or heteroaryl. “Substituted sulfoxide” refers to a group —S(O)R,in which R is substituted alkyl, substituted aryl, or substitutedheteroaryl, as defined herein.

The term “sulfone” refers to a group —S(O)₂R, in which R is alkyl, aryl,or heteroaryl. “Substituted sulfone” refers to a group —S(O)₂R, in whichR is substituted alkyl, substituted aryl, or substituted heteroaryl, asdefined herein.

The term “keto” or “oxo” refers to a group —C(O)—.

The term “thiocarbonyl” refers to a group —C(S)—.

The term “carboxy” refers to a group —C(O)—OH.

The term “optional” or “optionally” mean that the subsequently describedevent or circumstance may or may not occur, and that the descriptionincludes instances where said event or circumstance occurs and instancesin which it does not.

The term “substituted” includes embodiments in which a monoradicalsubstituent is bound to a single atom of the substituted group (e.g.forming a branch), and also includes embodiments in which thesubstituent may be a diradical bridging group bound to two adjacentatoms of the substituted group, thereby forming a fused ring on thesubstituted group.

Where a given group (moiety) is described herein as being attached to asecond group and the site of attachment is not explicit, the given groupmay be attached at any available site of the given group to anyavailable site of the second group. For example, a “loweralkyl-substituted phenyl”, where the attachment sites are not explicit,may have any available site of the lower alkyl group attached to anyavailable site of the phenyl group. In this regard, an “available site”is a site of the group at which a hydrogen of the group may be replacedwith a substituent.

It is understood that in all substituted groups defined above, polymersarrived at by defining substituents with further substituents tothemselves (e.g., substituted aryl having a substituted aryl group as asubstituent which is itself substituted with a substituted aryl group,etc.) are not intended for inclusion herein. Also not included areinfinite numbers of substituents, whether the substituents are the sameor different. In such cases, the maximum number of such substituents isthree. Each of the above definitions is thus constrained by a limitationthat, for example, substituted aryl groups are limited to substitutedaryl-(substituted aryl)-substituted aryl.

A compound of a given formula (e.g. the “compound of structural Formula(I)”) is intended to encompass the compounds of the disclosure, and thepharmaceutically acceptable salts, pharmaceutically acceptable esters,hydrates, polymorphs, and prodrugs of such compounds.

Additionally, the compounds of the disclosure may possess one or moreasymmetric centers and can be produced as a racemic mixture or asindividual enantiomers or diastereoisomers. The number of stereoisomerspresent in any given compound of a given Formula depends upon the numberof asymmetric centers present (there are 2n stereoisomers possible wheren is the number of asymmetric centers). The individual stereoisomers maybe obtained by resolving a racemic or non-racemic mixture of anintermediate at some appropriate stage of the synthesis, or byresolution of the compound by conventional means. The individualstereoisomers (including individual enantiomers and diastereoisomers) aswell as racemic and non-racemic mixtures of stereoisomers areencompassed within the scope of the present invention, all of which areintended to be depicted by the structures of this specification unlessotherwise specifically indicated.

The term “isomers” means different compounds that have the samemolecular formula. Isomers include stereoisomers, enantiomers, anddiastereomers.

The term “stereoisomers” means isomers that differ only in the way theatoms are arranged in space.

The term “enantiomers” means a pair of stereoisomers that arenon-superimposable mirror images of each other. A 1:1 mixture of a pairof enantiomers is a “racemic” mixture. The term “(±)” is used todesignate a racemic mixture where appropriate.

The term “diastereoisomers” means stereoisomers that have at least twoasymmetric atoms, but which are not mirror-images of each other.

Absolute stereochemistry is specified herein according to the CahnIngold Prelog R S system. When the compound is a pure enantiomer thestereochemistry at each chiral carbon may be specified by either R or S.Resolved compounds whose absolute configuration is unknown aredesignated (+) or (−) depending on the direction (dextro- or levorotary)that they rotate the plane of polarized light at the wavelength of thesodium D line.

Some of the compounds of the present disclosure exist as ‘tautomericisomers” or “tautomers.” “Tautomeric isomers” or “tautomers” are isomersthat are in equilibrium with one another. For example, amide containingcompounds may exist in equilibrium with imidic acid tautomers.Regardless of which tautomer is shown, and regardless of the nature ofthe equilibrium among tautomers, the compounds are understood by one ofordinary skill in the art to comprise both amide and imidic acidtautomers. Thus, the amide containing compounds are understood toinclude their imidic acid tautomers. Likewise, the imidic acidcontaining compounds are understood to include their amide tautomers.Non-limiting examples of amide-comprising and imidic acid-comprisingtautomers are shown below:

The term “polymorph” refers to different crystal structures of acrystalline compound. The different polymorphs may result fromdifferences in crystal packing (packing polymorphism) or differences inpacking between different conformers of the same molecule(conformational polymorphism).

The term “solvate” refers to a complex formed by combining a compoundand a solvent.

The term “hydrate” refers to the complex formed by combining a compoundand water.

The term “pharmaceutically acceptable salt” of a given compound refersto salts that retain the biological effectiveness and properties of thegiven compound, and which are not biologically or otherwise undesirable.In many cases, the compounds of this disclosure are capable of formingpharmaceutically acceptable acid and/or base salts by virtue of thepresence of amino and/or carboxyl groups or groups similar thereto.

Pharmaceutically acceptable base addition salts can be prepared frominorganic and organic bases. Salts derived from inorganic bases include,by way of example only, sodium, potassium, lithium, ammonium, calcium,and magnesium salts. Salts derived from organic bases include, but arenot limited to, salts of primary, secondary and tertiary amines, such asalkyl amines, dialkyl amines, trialkyl amines, substituted alkyl amines,di(substituted alkyl) amines, tri(substituted alkyl) amines, alkenylamines, dialkenyl amines, trialkenyl amines, substituted alkenyl amines,di(substituted alkenyl) amines, tri(substituted alkenyl) amines,cycloalkyl amines, di(cycloalkyl) amines, tri(cycloalkyl) amines,substituted cycloalkyl amines, disubstituted cycloalkyl amine,trisubstituted cycloalkyl amines, cycloalkenyl amines, di(cycloalkenyl)amines, tri(cycloalkenyl) amines, substituted cycloalkenyl amines,disubstituted cycloalkenyl amine, trisubstituted cycloalkenyl amines,aryl amines, diaryl amines, triaryl amines, heteroaryl amines,diheteroaryl amines, triheteroaryl amines, heterocyclic amines,diheterocyclic amines, triheterocyclic amines, mixed di- and tri-amineswhere at least two of the substituents on the amine are different andare selected from the group consisting of alkyl, substituted alkyl,alkenyl, substituted alkenyl, cycloalkyl, substituted cycloalkyl,cycloalkenyl, substituted cycloalkenyl, aryl, heteroaryl, heterocyclic,and the like. Also included are amines where the two or threesubstituents, together with the amino nitrogen, form a heterocyclic orheteroaryl group. Specific examples of suitable amines include, by wayof example only, isopropylamine, trimethyl amine, diethyl amine,tri(iso-propyl) amine, tri(n-propyl) amine, ethanolamine,2-dimethylaminoethanol, tromethamine, lysine, arginine, histidine,caffeine, procaine, hydrabamine, choline, betaine, ethylenediamine,glucosamine, N-alkylglucamines, theobromine, purines, piperazine,piperidine, morpholine, N-ethylpiperidine, and the like.

Pharmaceutically acceptable acid addition salts also may be preparedfrom inorganic and organic acids. Salts derived from inorganic acidsinclude hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid,phosphoric acid, and the like. Salts derived from organic acids includeacetic acid, propionic acid, glycolic acid, pyruvic acid, oxalic acid,malic acid, malonic acid, succinic acid, maleic acid, fumaric acid,tartaric acid, citric acid, benzoic acid, cinnamic acid, mandelic acid,methanesulfonic acid, ethanesulfonic acid, p-toluene-sulfonic acid,salicylic acid, and the like.

The terms “pharmaceutically acceptable carrier” or “pharmaceuticallyacceptable excipient” as used herein includes any and all solvents,dispersion media, coatings, antibacterial and antifungal agents,isotonic and absorption delaying agents and the like. The use of suchmedia and agents for pharmaceutically active substances is well known inthe art. Except insofar as any conventional media or agent isincompatible with the active ingredient, its use in the therapeuticcompositions is contemplated. Supplementary active ingredients can alsobe incorporated into the compositions.

Any formula or structure given herein, including Formula (I) and Formula(II), is also intended to represent unlabeled forms as well asisotopically labeled forms of the compounds. Isotopically labeledcompounds have structures depicted by the formulas given herein exceptthat one or more atoms are replaced by an atom having a selected atomicmass or mass number. Examples of isotopes that can be incorporated intocompounds of the invention include isotopes of hydrogen, carbon,nitrogen, oxygen, phosphorous, fluorine, and chlorine, such as, but notlimited to ²H (deuterium, D), ³H (tritium), ¹¹C, ¹³C, ¹⁴C, ¹⁵N, ¹⁸F,³¹P, ³²P, ³⁵S, ³⁶Cl, and ¹²⁵I. Various isotopically labeled compounds ofthe present invention, for example those into which radioactive isotopessuch as ³H, ¹³C, and ¹⁴C are incorporated. Such isotopically labelledcompounds may be useful in metabolic studies, reaction kinetic studies,detection, or imaging techniques, such as positron emission tomography(PET) or single-photon emission computed tomography (SPECT) includingdrug or substrate tissue distribution assays, or in radioactivetreatment of patients.

Deuterium labelled or substituted therapeutic compounds of the inventionmay have improved DMPK (drug metabolism and pharmacokinetics)properties, relating to distribution, metabolism, and excretion (ADME).Substitution with heavier isotopes such as deuterium may afford certaintherapeutic advantages resulting from greater metabolic stability, forexample increased in vivo half-life or reduced dosage requirements. An¹⁸F labeled compound may be useful for PET or SPECT studies.Isotopically labeled compounds of this invention and prodrugs thereofcan generally be prepared by carrying out the procedures disclosed inthe schemes or in the examples and preparations described below bysubstituting a readily available isotopically labeled reagent for anon-isotopically labeled reagent. Further, substitution with heavierisotopes, particularly deuterium (i.e., ²H or D) may afford certaintherapeutic advantages resulting from greater metabolic stability, forexample increased in vivo half-life or reduced dosage requirements or animprovement in therapeutic index. It is understood that deuterium inthis context is regarded as a substituent in the compound of the Formula(I).

The concentration of such a heavier isotope, specifically deuterium, maybe defined by an isotopic enrichment factor. In the compounds of thisinvention any atom not specifically designated as a particular isotopeis meant to represent any stable isotope of that atom. Unless otherwisestated, when a position is designated specifically as “H” or “hydrogen,”the position is understood to have hydrogen at its natural abundanceisotopic composition. Accordingly, in the compounds of this inventionany atom specifically designated as a deuterium (D) is meant torepresent deuterium.

In the description, including the Examples, all temperatures are indegrees Celsius (° C.), unless otherwise stated, and abbreviations andacronyms have the following meanings listed in Table 2 (below).

TABLE 2 Abbreviation Meaning AcOH Acetic acid ALDH-2 Human mitochondrialaldehyde dehydrogenase BHA Butylated hydroxy anisole Boctert-Butoxycarbonyl (Boc)₂O Di(tert-butyl) carbonate ° C. Degree CelsiusCbz Benzyl carbamate cm centimeter Cs₂CO₃ Cesium carbonate DA DopamineDBU 1,8-Diazabicyclo[5.4.0]undec-7-ene DCC Dicyclohexyl carbodiimide DCMDichloromethane DIC Diisopropyl carbodiimide DIEAN,N-Diisopropylethylamine DIPEA Diisopropylethylamine DMAP4-Dimethylaminopyridine DMF Dimethylformamide DMF Dimehtylformamide DMSODimethylsulfoxide EDTA Ethylenediaminetetraacetic acid equiv/eqEquivalents EtOAc Ethyl acetate EtOH Ethanol g Grams HATU(1-[Bis(dimethylamino)methylene]-1H-1,2,3- triazolo[4,5-b]pyridinium3-oxide hexafluorophosphate HPLC High-performance liquid chromatographyhrs/h Hours Hz Hertz IC₅₀ The half maximal inhibitory concentration IIDQ1-Isobutoxycarbonyl-2-isobutoxy-1,2-dihydro quinone ip IntraperitonealIV Intravenous J Coupling constant K₂CO₃ Potassium carbonate Kg KilogramKOAc Potassium acetate KOtBu Potassium tert-Butoxide L Liter LC-MSLiquid chromatography-mass spectrometry LG Leaving group M Molar m/zmass-to-charge ratio M+ Mass peak M + H Mass peak plus hydrogen M + NaMass peak plus sodium MAO Monoamine oxidase Me Methyl MeOH Methanol mgMilligram MHz Megahertz min Minute mL (or ml) Milliliter mM Millimolarmmol Millimole MS Mass spectroscopy MTBE Methyl tert-butyl ether MWMicrowave Na₂CO₃ Sodium carbonate NaBH₄ Sodium borohydride NADNicotinamide Adenine Dinucleotide NaOH Sodium hydroxide NMMN-Methylmorpholine NMP N-Methyl-2-pyrrolidone NMR Nuclear magneticresonance PG Protecting group Ph Phenyl q.s. Quantity sufficient toachieve a stated function rt Room temperature S Second SC SubcutaneousSEM Standard error of means TEA Triethylamine THF Tetrahydrofuran TLCThin layer chromatography TMS Trimethylsily1 TMSCl Trimethysilylchloride Tris tris(hydroxymethyl)aminomethane δ Chemical shift μgMicrogram μL (or μl) Microliter μM Micromolar μmol Micromole

ALDH-2 Inhibitor Compounds

Compounds that act as selective inhibitors of ALDH-2 have been shown toreduce pathophysiologic dopamine surge. See e.g., Yao et al.,“Inhibition of aldehyde dehydrogenase-2 suppresses cocaine seeking bygenerating THP, a cocaine use-dependent inhibitor of dopaminesynthesis,” Nature Medicine (2010), Vol. 16, No. 9; Diamond and Yao,“From Ancient Chinese Medicine to a Novel Approach to Treat CocaineAddiction,” CNS & Neurological Disorders Drug Targets (2015) Vol. 14,No. 6. Selective inhibitors of ALDH-2 have also demonstrated the abilityto suppress self-administration of nicotine in rats. See e.g., Rezvaniet al., “Inhibition of Aldehyde Dehydrogenase-2 (ALDH-2) SuppressesNicotine Self-Administration in Rats,” (2015) Journal of Drug andAlcohol Research, vol. 4: 1-6; Kim et al. “Brain Microdialysis Coupledto LC-MS/MS Revealed That CVT-10216, a Selective Inhibitor of AldehydeDehydrogenase 2, Alters the Neurochemical and Behavioral Effects ofMethamphetamine,” (2021) ACS Chem Neurosci, Vol. 12: 1552-1562; and U.S.Pat. Nos. 8,558,001, 8,575,353, 9,000,015, 9,610,299; Int'l Pat. Publ.WO2013/006400. The novel ALDH-2 inhibitor compounds provided in thepresent disclosure have been shown to selectively inhibit ALDH-2 inpreclinical assays and to exhibit characteristics of lowered hepatoxicliability. Accordingly, the compounds of the present disclosure can beuseful for the treatment of conditions responsive to the selectiveinhibition of ALDH-2 and the reduction of pathophysiologic dopaminesurge. Such uses can include the reduction and/or prevention ofaddiction in mammals to substances or conditions of abuse or addictionincluding alcohol, nicotine, cocaine, methamphetamine, opioids,compulsive eating disorder, and/or anxiety disorder, each individuallyor concurrently.

In at least one embodiment, the present disclosure provides an ALDH-2inhibitor compound of structural Formula (I):

-   -   wherein:        -   X¹ is N or CR³;        -   each of X² and X³ is independently N or CR¹⁰;        -   R¹¹ is H, halogen, optionally substituted C₁₋₆ alkyl, or            cycloalkyl;        -   R⁷ is H, or optionally substituted C₁₋₆ alkyl;        -   each of R², R³, R⁴, R⁵, R⁶, R⁸, R⁹, and R¹⁰ is independently            H, halogen, —CF₃, —OH, —CH₂OH, —CN, optionally substituted            alkyl, optionally substituted alkylene, optionally            substituted alkynyl, optionally substituted alkoxy,            optionally substituted cycloalkyl, optionally substituted            aryl, optionally substituted aralkyl, optionally substituted            heteroaryl, optionally substituted heteroaralkyl, optionally            substituted heterocyclyl, aminocarbonyl, acyl, acylamino,            —O—(C₁ to C₆-alkyl)-O—(C₁ to C₆-alkyl),            —CH₂OP(O)(OR²⁰)(OR²¹), —SO₂NR²⁴R²⁵; or —NR²⁴R²⁵, with the            proviso that R² and R⁶ are not both Cl when X¹ is CR³, X² is            CR⁴, X³ is CR⁶, X⁴ is CR¹⁰, X⁵ are CR¹⁰, and R¹¹ is H;        -   each of R²⁰ and R²¹ is independently Na⁺, Li⁺, K⁺, hydrogen,            C₁₋₆ alkyl; or R²⁰ and R²¹ can be combined to represent a            single divalent cation Zn²⁺, Ca²⁺, or Mg²⁺ and each of R²⁴            and R²⁵ is independently chosen from hydrogen or C₁₋₆ alkyl            or when combined together with the nitrogen to which they            are attached form a heterocycle;    -   or a pharmaceutically acceptable salt, ester, single        stereoisomer, mixture of stereoisomers, or a tautomer thereof.

As illustrated by the exemplary compounds (1a), (1b), (1c), (1d), (1e),(1f), (1g), (1h), (1i), (1j), (1k), (1l), (1m), and (1n), a wide rangeof specific ALDH-2 inhibitor compound structures within structuralFormula (I) are contemplated, including pharmaceutically acceptablesalts, esters, single stereoisomers, mixtures of stereoisomers, ortautomers of the compounds, and compounds having one or more of thefollowing structural features: (i) each of R², R³, R⁴, R⁵, R⁷, R⁸, R⁹,R¹⁰, and R¹¹ are H; (ii) X¹ is CR³, X² is CR⁴, and X³ is CR⁶; (iii) X¹is N, X² is CR⁴, and X³ is CR⁶; (iv) X¹ is CR³, X² is N, and X³ is CR⁶;(v) X¹ is CR³, X² is CR⁴, and X³ is N; (vi) X⁴ is CR¹⁰, and X⁵ is CR¹⁰;(vii) X⁴ is CR¹⁰, and X⁵ is N; (viii) X⁴ is N, and X⁵ is N; (ix) X¹ isCR³, X² is CR¹⁰, and X³ is CR¹⁰; (x) R² is selected from H, Cl, F, orCH₃; (xi) R³ is selected from H, Cl, F, and CH₃; (xii) R⁵ is selectedfrom H, Cl, F, and CH₃; (xiii) R⁶ is selected from H, Cl, F, and CF₃;(xiv) R¹¹ is selected from H and halogen; and/or (xv) R¹¹ is a 3-fluoro.

In at least one embodiment, the present disclosure provides an ALDH-2inhibitor compound of structural Formula (II):

-   -   wherein,        -   each of X² and X³ are independently N or CH;        -   R¹¹ is H, halogen, optionally substituted C₁₋₆ alkyl, or            cycloalkyl;        -   R¹ is selected from

-   -   -   each of R², and R⁶, is independently H, Br, Cl, F, CH₃, or            CF₃; and        -   each of R³, R⁴, and R⁵, is independently H, Br, Cl, F, CH₃,            CF₃, —OH, —CH₂OH, —CN, optionally substituted alkyl,            optionally substituted alkylene, optionally substituted            alkynyl, optionally substituted alkoxy, optionally            substituted cycloalkyl, optionally substituted aryl,            optionally substituted aralkyl, optionally substituted            heteroaryl, optionally substituted heteroaralkyl, optionally            substituted heterocyclyl, aminocarbonyl, acyl, acylamino,            —O—(C₁ to C₆-alkyl)-O—(C₁ to C₆-alkyl),            —CH₂OP(O)(OR²⁰)(OR²¹), —SO₂NR²⁴R²⁵; or —NR²⁴R²⁵, with the            proviso that R² and R⁶ are not both Cl when when R¹ is an            aromatic ring, X² and X³ are CH, and R¹¹ is H;

    -   or a pharmaceutically acceptable salt, ester, single        stereoisomer, mixture of stereoisomers, or a tautomer thereof.

As illustrated by the exemplary compounds (1a), (1b), (1c), (1d), (1e),(1f), (1g), (1h), (1i), (1j), (1k), (1l), (1m), and (1n), a wide rangeof specific ALDH-2 inhibitor compound structures within structuralFormula (II) are contemplated, including pharmaceutically acceptablesalts, esters, single stereoisomers, mixtures of stereoisomers, ortautomers of the compounds, and compounds having one or more of thefollowing structural features: (i) X² and X³ are CH; (ii) X² is CH andX³ is N; (iii) R¹¹ is H; (iv) R¹¹ is 3-fluoro; (v) R³, R⁴, and R⁵ are H;(vi) R³, R⁴, and R⁵ are independently H, Cl, F, CH₃, or CF₃; (vii) R² isH, Cl, F, or CH₃; (viii) R⁶ is H, Br, Cl, F, or CF₃; and/or (ix) R¹ isselected from:

The ALDH-2 inhibitor compounds of structural Formulas (I) and (II) canbe prepared from readily available starting materials using methods andprocedures known in the art. In particular, the present disclosureprovides general synthetic strategies for preparing compounds ofstructural Formula (I) and structural Formula (II), and also exemplifiesspecific synthesis protocols that can be used to prepare the exemplarycompounds (1a), (1b), (1c), (1d), (1e), (1f), (1g), (1h), (1i), (1j),(1k), (1l), (1m), (1n), and (1o), described herein and listed in Table1.

Briefly, the compounds of Formula (I) or (II) may be prepared accordingto the synthetic sequence shown in Scheme A

wherein, substituents R¹ through R¹¹, X¹ through X³ are as definedherein, and LG is a leaving group (e.g., halogen, hydroxyl, alkoxy,OSO₂CF₃, N₂ ⁺, etc.).

The Scheme A reactants (a) and (b) are commercially available or can beprepared as described in the Examples below, or by means well known inthe art. In general, the reactants (a) and at least one molarequivalent, and preferably a slight excess (e.g., 1.2 to 1.5 molarequivalents) of (b), as shown in Scheme A, are combined under standardreaction conditions in an inert solvent, such as dichloromethane (DCM)or dimethylformamide (DMF), at a temperature of about 0° C. to about 25°C. until the reaction is complete, generally about 30 minutes to about 2hours. Standard reaction conditions further comprise the use of a molarexcess of suitable base, such as triethylamine (TEA),diisopropylethylamine (DIPEA), N-methylmorpholine (NMM), sodium orpotassium hydroxide, or pyridine, or in some cases where LG is hydroxyl,a peptide coupling reagent, such asO-(7-azabenzotriazol-1-yl)-N,N,N,N′-tetra methyluroniumhexafluorophosphate (HATU), may be used. When the reaction to form theintermediate (c) is substantially complete, it is subjected to standardconditions (e.g., heat and acid) to convert the methoxy group of (c) tothe oxo product (d). The product may be subjected, if necessary, to afurther deprotection sequence under standard reaction conditions (e.g.,THF, CH₂Cl₂, or the like, a molar excess of acid such as acetic acid,formic acid, trifluoroacetic acid, or the like as described herein) toyield isolated by conventional means.

Phosphate ester derivatives of compounds of Formula (I) or Formula (II)at the R¹¹ substituent may be prepared as shown below in the syntheticsequence of Scheme B.

For example, phosphate ester derivatives (i) can be prepared accordingto the synthetic sequence of Scheme B by the alkylation of apyridin-2(1H)-one (d) with at least one equivalent, and preferably aslight excess (e.g., 1.2 to 1.5 molar equivalents) of linker (e),wherein R¹² is an optionally substituted alkylene moiety of 1-6 carbonatoms, and at least one equivalent, and preferably a slight excess(e.g., 1.2 to 2 molar equivalents) of a suitable base such astriethylamine (TEA), diisopropylethylamine (DIPEA), N-methylmorpholine(NMM), or pyridine under standard reaction conditions to yield thealkylated derivative (f). This derivative (f) can subsequently be usedto O-alkylate a molar excess (e.g., 1.2 to 5 molar equivalents) ofphosphate diester (g) to yield the corresponding phosphate triester (h).Deprotection of phosphate triester (h) under standard conditions (e.g.,CH₃CN/H₂O or the like, a molar excess of acid such as acetic acid or thelike with heating, as described herein) yields phosphate ester (i).Phosphate esters of ALDH-2 inhibitor compounds have been shown to beuseful as prodrugs via in vivo hydrolysis of the phosphate ester. Seee.g., U.S. Pat. No. 8,558,001, which is hereby incorporated by referenceherein.

It will be appreciated that where typical or preferred processconditions (i.e., reaction temperatures, times, mole ratios ofreactants, solvents, pressures, etc.) in the Examples herein, otherprocess conditions can also be used unless otherwise stated. Optimumreaction conditions may vary with the particular reactants or solventused, but such conditions can be determined by one skilled in the art byroutine optimization procedures. Additionally, as will be apparent tothose skilled in the art, conventional protecting groups may benecessary to prevent certain functional groups from undergoing undesiredreactions. For example, a protecting group may be used to allow afunctional group (such as O, S, or N) to be temporarily blocked so thata reaction can be carried out selectively at another reactive site in amultifunctional compound. Protecting groups useful in syntheses of thepresent disclosure are well known in the art and include those describedin detail in Protective Groups in Organic Synthesis, Fourth Ed., Greene,T. W. and Wuts, P. G., Eds., John Wiley & Sons, New York: 2007, theentire contents of which are hereby incorporated by reference, andreferences cited therein.

As noted above, starting materials for the synthetic reaction Scheme Aare as disclosed in the Examples herein, are commercially available, orare generally known compounds that can be prepared by known proceduresor obvious modifications thereof. For example, many of the startingmaterials are available from commercial suppliers such as AldrichChemical Co. (Milwaukee, Wisconsin, USA), Bachem (Torrance, California,USA), Emka-Chemie or Sigma (St. Louis, Missouri, USA). Others may beprepared by procedures, or obvious modifications thereof, described instandard reference texts such as Fieser and Fieser's Reagents forOrganic Synthesis, Volumes 1-15 (John Wiley, and Sons, 1991), Rodd'sChemistry of Carbon Compounds, Volumes 1-5, and Supplementals (ElsevierScience Publishers, 1989), Organic Reactions, Volumes 1-40 (John Wiley,and Sons, 1991), March's Advanced Organic Chemistry, (John Wiley, andSons, 5th Edition, 2001), and Larock's Comprehensive OrganicTransformations (VCH Publishers Inc., 1989).

Uses and Methods of Treatments

The present disclosure also provides uses of the ALDH-2 inhibitorcompounds of structural Formulas (I) or (II) of the present disclosure,including uses in pharmaceutical compositions, which compositions can beused in methods for treatment and/or prevention of addiction orsubstance abuse in mammals, including addiction to or conditions ofabuse of alcohol, nicotine, cocaine, methamphetamine, and/or opioids,and/or a compulsive eating disorder, and/or an anxiety disorder, eachindividually or concurrently. The primary factor in the development ofconditions of abuse or addiction is neurophysiologic reinforcement(reward). Animal studies suggest the existence of at least one centralreward-reinforcement pathway for drug self-administration in the humanbrain (Volkow 2016). This pathway involves dopaminergic neurons thatoriginate in the ventral tegmental area (VTA) and project into thenucleus accumbens (NAc) and forebrain. Release of dopamine from theseneurons onto the dopamine receptors in the Nac produces positivereinforcement.

All known addictive drugs activate reward regions in the brain bycausing sharp increases in the release of dopamine (DA) to elicit areward signal that triggers associative learning or conditioning. Inthis type of Pavlovian learning, repeated experiences of reward becomeassociated with the environmental stimuli that precede them. Withrepeated exposure to the same reward, dopamine cells stop firing inresponse to the reward itself and instead fire in an anticipatoryresponse to the conditioned stimuli (referred to as “cues”) that in asense predict the delivery of the reward. Addictive drugs circumventnatural satiation of a ‘natural reward’ such as food or sex by directlyincreasing dopamine—a factor that may explain why compulsive behaviorsare more likely to emerge when people use drugs than when they pursue anatural reward.

It is well-established that cocaine and other addictive substances orconditions stimulate an increase in DA levels in the Nac, which appearsto mediate reward or reinforcement processes in brain (DiChiara 1988)(Boileau 2003) (Tizabi 2002). Volkow and Koob (Volkow 2016) provideevidence that a surge of dopamine (DA) drives craving and addictivebehavior through reward circuits (Feltenstein and See 2008). Conditionedresponses that trigger craving for addictive substances motivatebehaviors that often lead to heavy substance use, and these strongcravings can persist long after use has stopped (Volkow 2016).

While not wishing to be bound by theory, ALDH-2 inhibitors, such as thecompounds of structural Formulas (I) and (II) of the presentdisclosure), are effective in reducing or preventing surges in dopaminelevels caused by administration of a substance or conditions of abuseincluding alcohol, nicotine, cocaine, methamphetamine, opioids,compulsive eating disorder, and/or anxiety disorder. Therefore, ALDH-2inhibitors of the present disclosure can be administered to a mammal asa method to treat, reduce, and/or prevent addiction in a mammalreceiving the treatment.

Accordingly, it is contemplated that the ALDH-2 inhibitors comprising acompound of structural Formula (I) or Formula (II), or apharmaceutically acceptable salt, ester, single stereoisomer, mixture ofstereoisomers, or a tautomer of such a compound, can be used in therapy.For example, the inhibitor compounds of the present disclosure can beused as a pharmaceutical composition or medicament, and that thesecompositions can be used in treating conditions affected by inhibitionof ALDH-2. For example, the use in the treatment of chemical dependencyon a substance, use in treatment of a condition of addiction or abuse,use in treatment of a compulsive eating disorder, or use in treatment ofan anxiety disorder.

Further, the present disclosure also contemplates the use of the ALDH-2inhibitors comprising a compound of structural Formula (I) or Formula(II), or a pharmaceutically acceptable salt, ester, single stereoisomer,mixture of stereoisomers, or a tautomer of such a compound, in themanufacture of pharmaceutical compositions or medicaments. For example,pharmaceutical compositions or medicaments for the treatment of chemicaldependency on a substance, for use in treating a condition of addictionor abuse, for use in treating a compulsive eating disorder, or for usein treating an anxiety disorder.

In at least one embodiment, it is contemplated that the methods can beused to treat any mammal that needs therapy for a condition such asaddiction. In particular it is contemplated that the method can be usedwherein the mammal is a human. Accordingly, in at least one embodiment,the present disclosure provides a method for treatment, or prevention ofthe acquisition of, addiction to substances or conditions of abuse in amammal wherein the method comprises administering to the mammal atherapeutically effective amount of an ALDH-2 inhibitor, wherein theALDH-2 inhibitor is a compound of structural Formula (I) or Formula(II), or a pharmaceutically acceptable salt, ester, single stereoisomer,mixture of stereoisomers, or a tautomer of such a compound. In at leastone embodiment, the compound administered can be a compound selectedfrom compounds (1a), (1b), (1c), (1d), (1e), (1f), (1g), (1h), (1i),(1j), (1k), (1l), (1m), and (1n), or a pharmaceutically acceptable salt,ester, single stereoisomer, mixture of stereoisomers, or a tautomer ofsuch a compound.

In the at least one embodiment of the method, the step of administeringthe ALDH-2 inhibitor can comprise administering a pharmaceuticalcomposition, wherein the pharmaceutical composition comprises themedication, the ALDH-2 inhibitor, and a pharmaceutically acceptablecarrier.

In some embodiments of such methods of treatment, the method comprisesself-administering a therapeutically effective dose of an ALDH-2inhibitor to reduce the urge to use a substance of abuse such asalcohol, nicotine, cocaine, methamphetamine, opioids, or food. In someembodiments, it is contemplated that the ALDH-2 inhibitor compound inthe form of a pharmaceutical composition is administered (includingself-administered) as a once- or a twice-a-day dose. In someembodiments, the once-a-day dose is in a formulation (e.g., a tablet),that is self-administered by the subject or patient.

In some embodiments for treatment of addiction, it is contemplated thatadministration of the ALDH-2 inhibitor compound to the subject cancontinue for at least 1 month, at least 3 months, at least 6 months, atleast 1 year, or forever.

In various embodiments of the methods disclosed herein for the safetreatment, or prevention of the acquisition, of addiction to substancesor conditions of abuse in a mammal, the ALDH-2 inhibitor has lowhepatotoxic liability and/or is not hepatotoxic. It has been reportedthat an assay using HepaRG® spheroids can be used to determine thehepatotoxic potential or liability of drug candidates. See e.g., Walkeret al., “The evolution of strategies to minimise the risk of humandrug-induced liver injury (DILI) in drug discovery and development,”(2020) Archives of Toxicology, Vol. 94: 2559-2585, which is herebyincorporated by reference herein in its entirety. Walker et al. havereported that results from HepaRG spheroid assays are correlated withdrugs known to cause hepatoxicity in humans with high sensitivity,specificity, and accuracy of 84%, 100%, and 89%, respectively, when acut-off minimum effective concentration (MEC)<25×C_(max.tot) is applied(C_(max.tot) is the maximal total plasma concentration of drug, and MECis the concentration that significantly crosses the vehicle controlthreshold of a cell health marker). In applying the HepaRG spheroidassay analysis to determining the hepatoxic liability of ALDH-2inhibitor compounds, consideration is made of the binding to plasmaprotein and the limitations to CNS penetration due to the blood-brainbarrier. Thus, it is reasonable to assument a multiple of 100 indetermining a most preferred ratio of MEC to IC₅₀ (ALDH-2) for ALDH-2inhibitor compounds that exhibit low hepatotoxic liability. Accordingly,exemplary ratios of HepaRG spheroids assay MEC to the ALDH-2 inhibitorassay IC₅₀ indicating low hepatotoxic liability are most preferred tobe >2500, followed by >250, and then >25 would be least preferred.

Pharmaceutical Compositions

In some embodiments of the methods of the present disclosure, it iscontemplated that the ALDH-2 inhibitor is administered in the form of apharmaceutical composition. The pharmaceutical composition comprising anALDH-2 inhibitor includes a dosage comprising a therapeuticallyeffective amount of the active ingredient, such as an ALDH-2 inhibitorcompound of structural Formula (I) or Formula (II), or apharmaceutically acceptable salt ester, single stereoisomer, mixture ofstereoisomers, or tautomer thereof, and one or more pharmaceuticallyacceptable excipients, carriers, including inert solid diluents andfillers, diluents, including sterile aqueous solution and variousorganic solvents, permeation enhancers, solubilizers and adjuvants.

As disclosed elsewhere herein, in some embodiments of the methods thestep of administering can comprise administering a pharmaceuticalcomposition, wherein the pharmaceutical composition contains an ALDH-2inhibitor of structural Formula (I) or (II) (e.g., compounds (1a), (1b),(1c), (1d), (1e), (1f), (1g), (1h), (1i), (1j), (1k), (1l), (1m), (1n)),or a pharmaceutically acceptable salt, ester, single stereoisomer,mixture of stereoisomers, or a tautomer of such a compound, and apharmaceutically acceptable carrier. Accordingly, in some embodimentsthe present disclosure also provides a pharmaceutical composition,wherein the composition comprises a therapeutically effective amount ofan ALDH-2 inhibitor and a pharmaceutically acceptable carrier.

In some embodiments, the pharmaceutical composition useful in themethods of the present disclosure is in a unit dosage form, such as adosage form that contains the active ingredient (e.g., compound (1a)) ina single dosage form.

In some embodiments, the present disclosure provides a dosage formcomprising a pharmaceutical composition of an ALDH-2 inhibitor (e.g.,compound (1a)) and a pharmaceutically acceptable carrier, wherein thedosage form comprises ALDH-2 inhibitor in a therapeutically effectiveamount.

In some embodiments, the pharmaceutical composition comprises a dosageof an ALDH-2 inhibitor of Formula (I) in an amount of about 25 mg toabout 1200 mg, about 50 mg to about 600 mg, about 25 mg to about 400 mg,or about 25 mg to about 200 mg. In some embodiments, the pharmaceuticalcomposition comprises a dosage of an ALDH-2 inhibitor of Formula (I) inan amount of about 25 mg, about 50 mg, about 100 mg, about 200 mg, about300 mg, about 400 mg, about 500 mg, about 600 mg, about 800 mg, about1000 mg, or about 1200 mg.

Such pharmaceutical compositions can be prepared using methods wellknown in the pharmaceutical art (see, e.g., Remington's PharmaceuticalSciences, Mace Publishing Co., Philadelphia, PA 17th Ed. (1985) andModern Pharmaceutics, Marcel Dekker, Inc. 3rd Ed. (G. S. Banker & C. T.Rhodes, Eds.). Methods of preparing pharmaceutical compositions ofALDH-2 inhibitor compounds are described in the present disclosure,including the Examples disclosed herein. Useful synthetic methods forALDH-2 inhibitor compounds are also described in e.g., U.S. Pat. Nos.7,951,813, 8,158,810, 8,673,966, 8,558,001, 8,575,353, 9,000,015, and9,610,299, each of which is hereby incorporated by reference herein.

Modes of Administering ALDH-2 Inhibitors

In the methods of the present disclosure it is contemplated that thepharmaceutical composition(s) comprising the ALDH-2 inhibitor compounds,such as a compound of Formula (I) or Formula (II) (e.g., compounds (1a),(1b), (1c), (1d), (1e), (1f), (1g), (1h), (1i), (1j), (1k), (1l), (1m),(1n)), or a pharmaceutically acceptable salt, ester, singlestereoisomer, mixture of stereoisomers, or a tautomer of such acompound, can be administered either as single or multiple doses, and byany of the accepted modes of administration of active ingredients havingsimilar utility. For example, as described in U.S. Pat. No. 8,558,001, apharmaceutical composition comprising an ALDH-2 inhibitor can beadministered using a variety of different modes including rectal,buccal, intranasal, and transdermal routes, by intra-arterial injection,intravenously, intraperitoneally, parenterally, intramuscularly,subcutaneously, orally, topically, as an inhalant, or via an impregnatedor coated device such as a stent, for example, or an artery-insertedcylindrical polymer.

One exemplary route for administering that is useful in the methods ofthe present disclosure is oral. Oral administration may be via capsule,enteric coated tablets, or the like. Typically, in making thepharmaceutical compositions that include a medication containing anALDH-2 inhibitor, such as compound of Formula (I) or Formula (II), theactive ingredient(s) is diluted by an excipient and/or enclosed within acarrier in the form of a capsule, sachet, paper, or other container.When the excipient serves as a diluent, it can be a solid, semi-solid,or liquid material (as above), which acts as a vehicle, carrier ormedium for the active ingredient. Thus, the pharmaceuticalcomposition(s) suitable for administering in the methods of thedisclosure can be in the dosage form of tablets, pills, powders,lozenges, sachets, cachets, elixirs, suspensions, emulsions, solutions,syrups, aerosols (as a solid or in a liquid medium), ointmentscontaining, for example, up to 10% by weight of the active compound,soft and hard gelatin capsules, sterile injectable solutions, andsterile packaged powders.

Suitable excipients for use in the pharmaceutical compositionscomprising ALDH-2 inhibitors of the present disclosure are well known inthe art and include lactose, dextrose, sucrose, sorbitol, mannitol,starches, gum acacia, calcium phosphate, alginates, tragacanth, gelatin,calcium silicate, microcrystalline cellulose, polyvinylpyrrolidone,cellulose, sterile water, syrup, and methyl cellulose. Thepharmaceutical compositions can additionally include lubricating agentssuch as talc, magnesium stearate, and mineral oil; wetting agents;emulsifying and suspending agents; preserving agents such as methyl- andpropylhydroxy-benzoates; sweetening agents; and flavoring agents.

Exemplary methods of preparing pharmaceutical compositions of ALDH-2inhibitors suitable for use in the methods of the present disclosure areprovided in the Examples.

The pharmaceutical compositions comprising ALDH-2 inhibitors useful inthe methods of the present disclosure can be formulated so as to providequick, sustained, or delayed release of the relevant active ingredientafter administration by employing procedures known in the art.Controlled release drug delivery systems for oral administration includeosmotic pump systems and dissolutional systems containing polymer-coatedreservoirs or drug-polymer matrix formulations. Examples of controlledrelease systems are given in e.g., U.S. Pat. Nos. 3,845,770; 4,326,525;4,902,514; and 5,616,345.

The pharmaceutical compositions comprising ALDH-2 inhibitors useful inthe methods of the present disclosure can also be formulated foradministration via transdermal delivery devices (e.g., “patches”). Suchtransdermal patches may be used to provide continuous or discontinuousinfusion of the pharmaceutical compositions in controlled amounts. Theconstruction and use of transdermal patches for the delivery ofpharmaceutical compositions is well known in the art. See, e.g., U.S.Pat. Nos. 5,023,252, 4,992,445 and 5,001,139. Such patches may beconstructed for continuous, pulsatile, or on demand delivery of thepharmaceutical composition(s). In some embodiments, the pharmaceuticalcomposition(s) useful in the methods of the present disclosure areformulated in a unit dosage form.

Generally, ALDH-2 inhibitor compounds, such as the compounds ofstructural Formula (I) or (II) of the present disclosure, are known tobe effective over a wide range of dosages and are administered as apharmaceutical composition in a pharmaceutically effective amount. Insome embodiments, for oral administration, each dosage unit containsfrom about 10 mg to 1 g of an ALDH-2 inhibitor compound of structuralFormula (I) or Formula (II), or a pharmaceutically acceptable salt,ester, single stereoisomer, mixture of stereoisomers, or a tautomer ofsuch a compound, in some embodiments from 25 mg to 1200 mg. In someembodiments, for parenteral administration, from 10 to 700 mg of anALDH-2 inhibitor compound, such as compound of structural Formula (I) orFormula (II), or a pharmaceutically acceptable salt, ester, singlestereoisomer, mixture of stereoisomers, or a tautomer of such acompound, or in some embodiments, from about 50 mg to 300 mg.

Generally, in the methods of the disclosure, the amount of the ALDH-2inhibitor compound, such as compound of structural Formula (I) or (II),or a pharmaceutically acceptable salt, ester, single stereoisomer,mixture of stereoisomers, or a tautomer of such a compound, to beadministered will be determined by a physician, in view of relevantcircumstances of the subject being so treated, the chosen route ofadministration, and of course, the age, the weight, the severity ofsymptoms, the response of the individual subject to the treatment, andthe like.

For preparing a solid pharmaceutical composition useful in the methodsof the present disclosure, the active ingredient is mixed with apharmaceutical excipient to form a solid preformulation compositioncontaining a homogeneous mixture of the active ingredient and theexcipients. When referring to these preformulation compositions ashomogeneous, it is meant that the active ingredient is dispersed evenlythroughout the composition so that the composition may be readilysubdivided into equally effective unit dosage forms such as tablets,pills, and capsules. Tablets or pills may be coated or otherwisecompounded to provide a dosage form affording the advantage of prolongedaction, or to protect from the acid conditions of the stomach. Forexample, the tablet or pill can comprise an inner dosage and an outerdosage component, the latter being in the form of an envelope over theformer. The two components can be separated by an enteric layer thatserves to resist disintegration in the stomach and permit the innercomponent to pass intact into the duodenum or to be delayed in release.A variety of materials can be used for such enteric layers or coatings,such materials including a number of polymeric acids and mixtures ofpolymeric acids with such materials as shellac, cetyl alcohol, andcellulose acetate.

Another exemplary mode for administering useful in the methods of thepresent disclosure is parenteral, particularly by injection.Pharmaceutical compositions of the present disclosure may beincorporated for administration by injection include aqueous or oilsuspensions, or emulsions, with sesame oil, corn oil, cottonseed oil, orpeanut oil, as well as elixirs, mannitol, dextrose, or a sterile aqueoussolution, and similar pharmaceutical vehicles. Aqueous solutions insaline are also conventionally used for injection. Ethanol, glycerol,propylene glycol, liquid polyethylene glycol, and the like (and suitablemixtures thereof), cyclodextrin derivatives, and vegetable oils may alsobe employed. The proper fluidity can be maintained, for example, by theuse of a coating, such as lecithin, by the maintenance of the requiredparticle size in the case of dispersion and by the use of surfactants.The prevention of the action of microorganisms can be brought about byvarious antibacterial and antifungal agents, for example, parabens,chlorobutanol, phenol, sorbic acid, thimerosal, and the like.

Sterile injectable solutions are prepared by incorporating the activeingredients of the present disclosure in the required amount in theappropriate solvent with various other ingredients as enumerated above,as required, followed by filtered sterilization. Generally, dispersionsare prepared by incorporating the various sterilized active ingredientsinto a sterile vehicle which contains the basic dispersion medium andthe required other ingredients from those enumerated above. In the caseof sterile powders for the preparation of sterile injectable solutions,the known methods of preparation include vacuum-drying and freeze-dryingtechniques which yield a powder of the active ingredient plus anyadditional desired ingredient from a previously sterile-filteredsolution thereof.

Pharmaceutical compositions that can be administered by inhalation orinsufflation include solutions and suspensions in pharmaceuticallyacceptable, aqueous organic solvents, or mixtures thereof, and powders.The liquid or solid compositions may contain suitable pharmaceuticallyacceptable excipients as described herein and as known in the art. Insome embodiments, the pharmaceutical composition of the ALDH-2 inhibitorcompound of structural Formula (I) or (II) (e.g., compounds (1a), (1b),(1c), (1d), (1e), (1f), (1g), (1h), (1i), (1j), (1k), (1l), (1m), (1n)),or a pharmaceutically acceptable salt, ester, single stereoisomer,mixture of stereoisomers, or a tautomer thereof, can be administered bythe oral or nasal respiratory route for local or systemic effect. Insome embodiments, the pharmaceutical compositions are prepared inpharmaceutically acceptable solvents which can be nebulized by use ofinert gases. These nebulized solutions can be inhaled directly from thenebulizing device or the nebulizing device may be attached to a facemask tent, or intermittent positive pressure breathing machine. In someembodiments, the pharmaceutical compositions useful in the methods canbe in solution, suspension, or powder compositions and can beadministered, orally or nasally, from devices that deliver theformulation in an appropriate manner.

EXAMPLES

Various features and embodiments of the disclosure are illustrated inthe following representative examples, which are intended to beillustrative, and not limiting. Those skilled in the art will readilyappreciate that the specific examples are only illustrative of theinvention as described more fully in the claims which follow thereafter.Every embodiment and feature described in the application should beunderstood to be interchangeable and combinable with every embodimentcontained within.

The following Examples 1-15 describe methods for the synthesis of theexemplary ALDH-2 inhibitor compounds of structural Formulas (I) and (II)depicted in Table 1 (above).

Reagents used in the syntheses of Examples 1-15 were purchased from thecommercial sources and were used as received. Other general methods andinstrumentation used in the syntheses of Examples 1-15 were as follows.¹H NMR spectra were obtained on a Bruker AVANCE 300 spectrometer at 300MHz and a Bruker AVANCE 400 spectrometer at 400 MHz withtetramethylsilane used as an internal reference. Thin-layerchromatography (TLC) was performed using Whatman No. 4500-101 (DiamondNo. MK6F silica-gel 60 Å) plates. Mass spectra were obtained on a WatersAcquity UPLC-MS spectrometer using electro spray ionization,detector-SQD, column-Acquity BEH-C18, 1.7 g, 2.1×50 mm, mobilephase-Acetonitrile: 10 mM Ammonium formate. HPLC analyses were performedon an Agilent 1200 series with PDA detector and Column Polaris C18-A,100×3.0 mm, and 2.6 μm. Chemical abbreviations used in the Examples areprovided in Table 2 (above).

Example 1: Synthesis of2-Chloro-6-methyl-N-(4-(6-oxo-1,6-dihydropyridin-2-yl)benzyl)benzamide(1a)

Compound 1a was prepared via the synthesis summarized in Scheme 1(below).

Step 1: Synthesis of tert-Butyl(4-(6-methoxypyridin-2-yl)benzyl)carbamate (2): To a degassed solutionof tert-butyl (4-bromobenzyl)carbamate (1) (1.30 g, 4.56 mmol) in 1,4dioxane:water (4:1) (36 mL), were added2-methoxy-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine (I)(1.40 g, 5.92 mmol), Cs₂CO₃ (4.44 g, 13.6 mmol) and Pd(dppf)Cl₂·CH₂Cl₂(372 mg, 0.456 mmol) at room temperature. The mixture was againde-gassed with Ar (g) for 5 min and heated at 100° C. for 5 h. Thesolvent was removed under reduced pressure. The residue was diluted withwater and extracted with EtOAc (2×100 mL). The organic layer wasseparated, washed with water and brine (100 mL), and dried over Na₂SO₄.The solvent was removed under reduced pressure. The residue was purifiedsilica gel chromatography (30% of EtOAc in hexanes) to afford tert-butyl(4-(6-methoxypyridin-2-yl)benzyl)carbamate (2) (900 mg, 63% yield) as anoff-white solid. ¹H NMR (400 MHz, DMSO-d₆): δ 8.04 (d, J=8.0 Hz, 2H),7.76 (q, J=7.6 Hz, J=8.4 Hz 1H), 7.53 (d, J=7.2 Hz, 1H), 7.43 (t, J=6.0Hz, 1H), 7.33 (d, J=8.0 Hz, 2H), 6.76 (dd, J=0.4 Hz, J=8.0 Hz, 1H), 4.17(d, J=6.0 Hz, 2H), 3.95 (s, 3H), 1.40 (s, 9H): MS (ESI+APCI; multimode):315 [M+H]⁺.

Step-2: Synthesis of (4-(6-Methoxypyridin-2-yl)phenyl)methanaminehydrochloride (3): To a stirred solution of tert-butyl(4-(6-methoxypyridin-2-yl)benzyl)carbamate (2) (0.9 g, 2.86 mmol), in2,2,2-trifluoroethanol (15 mL), was added TMSCl (1.55 g, 14.33 mmol) at0° C. under N₂ atmosphere. The reaction mixture was stirred at roomtemperature for 16 h. The solvent was removed under reduced pressure andMTBE added. The solids were filtered and washed with MTBE to afford(4-(6-methoxypyridin-2-yl)phenyl)methanamine hydrochloride (3) (650 mg,90% yield) as an off white solid. ¹H NMR (400 MHz, DMSO-d₆): δ 8.62(brs, 2H), 8.13 (d, J=8.4 Hz, 2H), 7.8 (t, J=7.2 Hz, 1H), 7.63-7.56 (m,3H), 6.80 (d, J=8.0 Hz, 1H), 4.07 (d, J=5.6 Hz, 2H), 3.96 (s, 3H).

Step 3: Synthesis of2-chloro-N-(4-(6-methoxypyridin-2-yl)benzyl)-6-methylbenzamide (4): To astirred solution of 4-(6-methoxypyridin-2-yl)phenyl)methanaminehydrochloride (3) (265 mg, 1.06 mmol) in CH₂Cl₂ (5.0 mL), were addedEt₃N (321 mg, 3.18 mmol) and 2-chloro-6-methylbenzoyl chloride (II) (200mg, 1.06 mmol) at 0° C. and allowed to stirred at rt for 5 h. Thereaction miture was diluted with water, basified with saturated aqueoussodium bicarbonate, and extracted with EtOAc (2×50 mL). The organiclayer was separated and washed with water and brine (1×50 mL) and driedover Na₂SO₄. The solvent was removed under reduced pressure. The residuewas purified by silica gel chromatography (30% of EtOAc in hexanes) toafford 2-chloro-N-(4-(6-methoxypyridin-2-yl)benzyl)-6-methylbenzamide(4). (200 mg, 51% yield) as off-white solid. ¹H NMR (400 MHz, DMSO-d₆):δ 9.07 (t, J=6.0 Hz, 1H), 8.08 (d, J=8.0 Hz, 2H), 7.77 (d, J=7.6 Hz,1H), 7.56 (d, J=7.6 Hz, 1H), 7.49 (d, J=8.4 Hz, 2H), 7.31-7.30 (m, 2H),7.23-7.21 (m, 1H), 6.77 (d, J=6.0 Hz, 1H), 4.51 (d, J=6.0 Hz, 2H), 3.96(s, 3H), 2.25 (s, 3H). MS (ESI+APCI; multimode): 367 [M+H]⁺, HPLC: 96.9(% of AUC).

Step-4: Synthesis of2-Chloro-6-methyl-N-(4-(6-oxo-1,6-dihydropyridin-2-yl)benzyl)benzamide(1a): To a stirred solution of2-chloro-N-(4-(6-methoxypyridin-2-yl)benzyl)-6-methylbenzamide (4) (160mg, 0.43 mmol) in 33% of HBr in CH₃COOH (3 mL) stirred at 100° C. for 16h. The reaction mixture was concentrated under reduced pressure andbasified with saturated aqueous NaHCO₃ up to pH 9-10. The reactionmixture was extracted with 10% CH₃OH in CH₂Cl₂ (2×50 mL). The organiclayer was dried over anhydrous Na₂SO₄. The solvent was removed underreduced pressure. The residue was purified by silica gel chromatography(10% CH₃OH in CH₂Cl₂) afford2-chloro-6-methyl-N-(4-(6-oxo-1,6-dihydropyridin-2-yl)benzyl)benzamide(1a) (100 mg, 65% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): 11.66 (brs, 1H), δ 9.08 (t, J=6.0 Hz, 1H), 7.76 (d, J=8.4 Hz,2H), 7.55-7.46 (m, 3H), 7.31-7.21 (m, 3H), 6.67 (s, 1H), 6.36 (d, J=8.8Hz, 1H), 4.50 (d, J=6.0 Hz, 2H), 2.24 (s, 3H). MS (ESI+APCI; multimode):353 [M+H]⁺, HPLC: 95.2 (% of AUC).

Example 2: Synthesis of2-Chloro-N-(4-(6-oxo-1,6-dihydropyridin-2-yl)benzyl)benzamide (1b)

Compound 1b was prepared via the synthesis summarized in Scheme 2(below).

Step-5: Synthesis of2-Chloro-N-(4-(6-methoxypyridin-2-yl)benzyl)benzamide (5): Prepared asin Example 1 (Step-3 in Scheme 1). The residue was purified by silicagel chromatography (30% EtOAc in hexanes) to afford2-chloro-N-(4-(6-methoxypyridin-2-yl)benzyl)benzamide (5) (200 mg, 71%yield) as an off-white solid. ¹H NMR (400 MHz, DMSO-d₆): δ 9.04 (t,J=6.0 Hz, 1H), 8.08 (d, J=4.4 Hz, 2H), 7.77 (t, J=3.6 Hz, 1H), 7.75-7.39(m, 7H), 6.77 (d, J=8.0 Hz, 1H), 4.50 (d, J=6.0 Hz, 2H), 3.96 (s, 3H).MS (ESI+APCI; multimode): 353 [M+H]⁺; HPLC: 98.0 (% of AUC).

Step-6: Synthesis of2-Chloro-N-(4-(6-oxo-1,6-dihydropyridin-2-yl)benzyl)benzamide (1b):Prepared as in Example 1 (Step-4 in Scheme 1). The residue was purifiedby silica gel chromatography (10% CH₃OH in CH₂Cl₂) to afford2-chloro-N-(4-(6-oxo-1,6-dihydropyridin-2-yl)benzyl)benzamide (1b) (70.0mg, 46% yield) as an off white solid. ¹H NMR (400 MHz, DMSO-d₆): δ 11.58(brs, 1H), 9.03 (t, J=5.6 Hz, 1H), 7.76 (d, J=8.0 Hz, 2H), 7.55-7.41 (m,7H), 6.67 (s, 1H), 6.36 (d, J=5.6 Hz, 1H), 4.49 (d, J=5.6 Hz, 2H). MS(ESI+APCI; multimode): 338 [M+H]⁺, HPLC: 95.6 (% of AUC).

Example 3: Synthesis of4-Chloro-2-methyl-N-(4-(6-oxo-1,6-dihydropyridin-2-yl)benzyl)nicotinamide(1c)

Compound 1c was prepared via the synthesis summarized in Scheme 3(below).

Step-7: Synthesis of4-Chloro-N-(4-(6-methoxypyridin-2-yl)benzyl)-2-methylnicotinamide 6): Toa stirred solution of 4-(6-methoxypyridin-2-yl)phenyl)methanaminehydrochloride (3) (600 mg, 2.40 mmol) in CH₂Cl₂ (20 mL), were addedi-Pr₂EtN (936 mg, 7.20 mmol) and 4-chloro-2-methylnicotinoyl chloride(IV) (541 mg, 2.88 mmol) at 0° C. and allowed to stirred at rt for 5 h.The reaction mixture was diluted with water, basified with saturatedaqueous sodium bicarbonate, and extracted with CH₂Cl₂ (2×50 mL). Theorganic layer was seperated and washed with water and brine (1×50 mL)and dried over Na₂SO₄. The solvent was removed under reduced pressure.The residue was purified by silica gel chromatography (90% EtOAc inhexanes) to afford4-chloro-N-(4-(6-methoxypyridin-2-yl)benzyl)-2-methylnicotinamide (6)(330 mg, 38% yield) as an off-white solid. ¹H NMR (400 MHz, DMSO-d₆): δ9.21 (t, J=6.0 Hz, 1H), 8.43 (d, J=5.2 Hz, 1H), 8.09 (d, J=8.4 Hz, 2H),7.77 (t, J=7.6 Hz, 1H), 7.57-7.55 (m, 1H), 7.48 (d, J=8.4 Hz, 2H), 7.45(dd, J=0.4 Hz, J=5.4.6 Hz, 1H), 6.77 (dd, J=0.4 Hz, J=8.4 Hz, 1H), 4.54(d, J=6.0 Hz, 2H), 3.96 (s, 3H), 2.44 (s, 3H): MS (ESI+APCI; multimode):368 [M+H], HPLC: 98.7 (% of AUC).

Step-8: Synthesis of4-Chloro-2-methyl-N-(4-(6-oxo-1,6-dihydropyridin-2-yl)benzyl)nicotinamide(1c): To a stirred solution of4-chloro-N-(4-(6-methoxypyridin-2-yl)benzyl)-2-methylnicotinamide (6)(160 mg, 0.43 mmol) in 4 M HCl in 1,4 dioxane (10 mL) and irridiated inmicrowave at 120° C. for 50 min. The reaction mixture was concentratedunder reduced pressure and basified with saturated aqueous NaHCO₃ up topH 9-10. The reaction mixture was extracted with 10% CH₃OH in CH₂Cl₂(2×50 mL). The organic layer was dried over anhydrous Na₂SO₄. Thesolvent was removed under reduced pressure. The residue was purified bysilica gel chromatography (15% CH₃OH in CH₂Cl₂) afford4-chloro-2-methyl-N-(4-(6-oxo-1,6-dihydropyridin-2-yl)benzyl)nicotinamide(1c) (110 mg, 70% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 11.70-11.43 (m, 1H), 9.22 (t, J=5.6 Hz, 1H), 8.43 (d, J=5.6Hz, 1H), 7.77 (d, J=7.6 Hz, 2H), 7.55-7.44 (m, 4H), 6.68 (brs, 1H), 6.36(d, J=9.2 Hz, 1H), 4.53 (d, J=6.0 Hz, 2H), 2.43 (s, 3H): MS (ESI+APCI;multimode): 354 [M+H]⁺: HPLC: 98.2 (% of AUC).

Example 4: Synthesis of2,6-dichloro-N-(4-(3-fluoro-6-oxo-1,6-dihydropyridin-2-yl)benzyl)benzamide(1d)

Compound 1d was prepared via the synthesis summarized in Scheme 4(below).

Synthesis of 24-dichlorobenzol chloride (V): To a stirred solution of2,4-dichlorobenzoic acid (20 g, 116 mmol) in anhydrous CH₂Cl₂ (500 mL)were added SOCl₂ (27.6 mL, 1570 mmol) and DMF (5 mL) at 0° C. under N₂atmosphere. The mixture was stirred to 55° C. for 16 h. The reactionmixture was concentrated under reduced pressure to afford crude2,4-dichlorobenzoyl chloride (I) (18 g. 86.12 mmol) as a colourlessliquid. The crude compound was directly used in the next step.

Step-9: Synthesis of N-(4-Bromobenzyl)-2,6-dichlorobenzamide (8): To astirred solution of (4-bromophenyl)methanamine (7) (18.0 g, 86.12 mmol)in CH₂Cl₂ (150 mL), were added Et₃N (24.1 mL, 17.22 mmol) and2,6-dichlorobenzoyl chloride (V) (16.0 g, 86.12 mmol) at 0° C. andallowed to stir at rt for 30 min. The reaction mixture was quenched withwater and extracted with CH₂Cl₂ (2×500 mL). The organic layer wasseparated washed with water and brine (2×500 mL) and dried over Na₂SO₄.The solvent was removed under reduced pressure and the residue waspurified by silica gel chromatography (50% of EtOAc in hexanes) toafford N-(4-Bromobenzyl)-2,6-dichlorobenzamide (8) (17.6 g, 53% yield)as an off-white solid. ¹H NMR (400 MHz, DMSO-d₆): δ 9.23 (t, J=6.0 Hz,1H), 7.56-7.42 (m, 5H), 7.36 (d, J=8.4 Hz, 2H), 4.44 (d, J=6.0 Hz, 2H).MS (ESI+APCI; multimode): 358.0 [M+H]+.

Step-10:2,6-Dichloro-N-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)benzamide(9); To a stirred solution of N-(4-bromobenzyl)-2,6-dichlorobenzamide(8) (5.00 g, 13.92 mmol) in 1,4 dioxane (50 mL), were added bispinacolate diborane (4.59 g, 18.10 mmol) and KOAc (3.14 g, 34.81 mmol)at room temperature. The mixture was de-gassed with Ar (g) for 10 min.Pd(dppf)Cl₂ (512 mg, 0.696 mmol) was added in one lot to the reactionmixture under N₂ atmosphere. The reaction mixture was stirred at 110° C.for 6 h. The solvent was concentrated under reduced pressure. Theresidue was diluted with water and extracted with EtOAc (2×50 mL). Theorganic layer was separated and washed with water and brine (2×50 mL)and dried over Na₂SO₄. The solvent was removed under reduced pressureand the residue was purified by silica gel chromatography (5% CH₃OH inCH₂Cl₂) to afford2,6-dichloro-N-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)benzamide(9) (4.00 g, 70% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 9.20 (t, J=6.0 Hz, 1H), 7.64 (d, J=8.0 Hz, 2H), 7.52-7.50(m, 2H), 7.45-7.40 (m, 3H) 4.48 (d, J=6.0 Hz, 2H), 1.29 (s, 12H). MS(ESI+APCI; multimode): 406.0 [M+H]⁺.

Step-11: Synthesis of 2-Bromo-6-(tert-butoxy)-3-fluoropyridine (11): Toa stirred solution of 2-bromo-3,6-difluoropyridine (10) (300 mg, 1.55mmol) in THF (5.0 mL), was added Potassiun tert-butoxide (3.10 mL, 3.10mmol) and stirred at rt for 16 h. The reaction mixture was diluted withwater and extracted with EtOAc (2×50 mL). The organic layer wasseparated and washed with water and brine (1×50 mL) and dried overNa₂SO₄. The solvent was removed under reduced pressure to afford2-bromo-6-(tert-butoxy)-3-fluoropyridine (11) (300 mg, 78% yield) acolorless liquid. ¹H NMR (400 MHz, DMSO-d₆): δ 7.76 (dd, J=8.0 Hz, 8.8Hz, 1H), 6.76 (dd, J=2.8 Hz, 8.8 Hz, 1H), 1.51 (s, 9H).

Step-12: Synthesis ofN-(4-(6-(tert-Butoxy)-3-fluoropyridin-2-yl)benzyl)-2,6-dichlorobenzamide(12): To a degassed solution of 2-bromo-6-(tert-butoxy)-3-fluoropyridine(11) (300 mg, 1.21 mmol) in 1,4 dioxane:water (4:1) (10 mL), were added2,6-dichloro-N-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)benzamide(9) (491 mg, 1.21 mmol), Cs₂CO₃ (789 mg, 2.42 mmol) andPd(dppf)Cl₂·CH₂Cl₂ (99 mg, 0.21 mmol) at room temperature. The mixturewas again de-gassed with Ar (g) for 5 min and irradiated in microwave at110° C. for 30 min. The solvent was removed under reduced pressure. Theresidue was diluted with water and extracted with EtOAc (2×50 mL). Theorganic layer was separated, washed with water and brine (1×50 mL), anddried over Na₂SO₄. The solvent was removed under reduced pressure. Theresidue was purified silica gel chromatography (20% of EtOAc in hexanes)to affordN-(4-(6-(tert-Butoxy)-3-fluoropyridin-2-yl)benzyl)-2,6-dichlorobenzamide(12) (160 mg, 29% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 9.22 (t, J=6.0 Hz, 1H), 7.87 (d, J=6.82 Hz, 2H), 7.71-7.66(m, 1H), 7.66-7.51 (m, 4H), 7.76-7.42 (m, 1H), 6.71 (dd J=2.4 Hz, 8.8Hz, 1H), 4.53 (d, J=6.0 Hz, 2H), 1.58 (s, 9H).

Step-13: Synthesis of2,6-Dichloro-N-(4-(3-fluoro-6-oxo-1,6-dihydropyridin-2-yl)benzyl)benzamide(Compound (1d)): To a stirred solution ofN-(4-(6-(tert-Butoxy)-3-fluoropyridin-2-yl)benzyl)-2,6-dichlorobenzamide(12) (150 mg, 0.33 mmol), in 2,2,2-trifluoroethanol (3.0 mL), was addedTMSCl (105 mg, 1.00 mmol) at room temperature under N₂ atmosphere Thereaction mixture was stirred at room temperature for 3 h. The solventwas removed under reduced pressure and MTBE added. The solids werefiltered and washed with MTBE to afford2,6-dichloro-N-(4-(3-fluoro-6-oxo-1,6-dihydropyridin-2-yl)benzyl)benzamide(1d) (50.0 mg, 38% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 11.0 (s, 1H), 9.25 (t, J=6.0 Hz, 1H), 7.81 (d, J=7.2 Hz,2H), 7.68-7.63 (m, 1H), 7.53-7.50 (m, 4H), 7.46-7.42 (m, 1H), 6.61 (dd,J=2.8 Hz, 8.8 Hz, 1H), 4.53 (d, J=6.0 Hz, 2H). MS (ESI+APCI; multimode):391 [M+H]⁺: HPLC: 98.2 (% of AUC).

Example 5: Synthesis of2-Chloro-N-(4-(3-fluoro-6-oxo-1,6-dihydropyridin-2-yl)benzyl)-6-methylbenzamide(1e)

Compound 1e was prepared via the synthesis summarized in Scheme 5(below).

Step-14: Synthesis of N-(4-Bromobenzyl)-2-chloro-6-methylbenzamide (13):To a stirred solution of (4-bromophenyl)methanamine (7) (2.00 g, 10.6mmol) in CH₂Cl₂ (30 mL), were added i-Pr₂EtN (4.10 g, 31.8 mmol) and2-chloro-6-methylbenzoyl chloride (II) (2.00 g, 10.6 mmol) at 0° C. andallowed to stir at rt for 12 h. The reaction mixture was diluted withwater, basified with saturated aqueous sodium bicarbonate, and extractedwith CH₂Cl₂ (2×100 mL). The organic layer was separated and washed withwater and brine (1×100 mL) and dried over Na₂SO₄. The solvent wasremoved under reduced pressure. The residue was purified by silica gelchromatography (60% EtOAc in hexanes) toN-(4-bromobenzyl)-2-chloro-6-methylbenzamide (13) (2.50 g, 69% yield) asan off white solid. ¹H NMR (400 MHz, DMSO-d₆): δ 9.05 (t, J=6.0 Hz, 1H),7.56-7.53 (m, 2H), 7.35-7.27 (m, 4H), 7.22-7.20 (m, 1H), 4.41 (d, J=6.0Hz, 2H), 2.21 (s, 3H); MS (ESI+APCI; multimode): 338 [M+H]⁺:

Step-15: Synthesis of2-Chloro-6-methyl-N-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)benzamide(14): To a degassed solution ofN-(4-bromobenzyl)-2-chloro-6-methylbenzamide (13) (1.00 g, 2.96 mmol) in1,4 dioxane (20 mL), were added4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi(1,3,2-dioxaborolane (1.12 g, 4.45mmol), KOAc (870 mg, 8.88 mmol) and Pd(dppf)Cl₂·CH₂Cl₂ (241 mg, 0.296mmol) at room temperature. The mixture was again de-gassed with Ar (g)for 5 min and heated at 110° C. for 5 h. The solvent was removed underreduced pressure. The residue was diluted with water and extracted withEtOAc (2×100 mL). The organic layer was separated, washed with water andbrine (1×50 mL), and dried over Na₂SO₄. The solvent was removed underreduced pressure. The residue was purified silica gel chromatography(60% of EtOAc in hexanes) to afford2-chloro-6-methyl-N-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)benzamide(14) (600 mg, 53% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 9.02 (t, J=6.0 Hz, 1H), 7.64 (d, J=8.0 Hz, 2H), 7.39 (d,J=8.0 Hz, 2H), 7.29 (t, J=2.8 Hz, 2H), 7.22-7.20 (m, 1H), 4.46 (d, J=6.0Hz, 2H), 2.22 (s, 3H), 1.29 (s, 12H). MS (ESI+APCI; multimode): 386[M+H]⁺:

Step-16: Synthesis of2-Chloro-N-(4-(3-fluoro-6-methoxypyridin-2-yl)benzyl)-6-methylbenzamide(16): To a degassed solution of2-chloro-6-methyl-N-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)benzamide(17) (300 mg, 0.77 mmol) in 1,4 dioxane:water (4:1) (10 mL), were added2-bromo-3-fluoro-6-methoxypyridine (18) (158 mg, 0.77 mmol), Cs₂CO₃ (506mg, 1.55 mmol) and Pd(dppf)Cl₂·CH₂Cl₂ (63.0 mg, 0.077 mmol) at roomtemperature. The mixture was again de-gassed with Ar (g) for 5 min andirridiated in microwave at 100° C. for 50 min. The solvent was removedunder reduced pressure. The residue was diluted with water and extractedwith EtOAc (2×50 mL). The organic layer was separated, washed with waterand brine (1×50 mL), and dried over Na₂SO₄. The solvent was removedunder reduced pressure. The residue was purified silica gelchromatography (50% of EtOAc in hexanes) to afford2-chloro-N-(4-(3-fluoro-6-methoxypyridin-2-yl)benzyl)-6-methylbenzamide(19) (200 mg, 66% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 9.08 (t, J=6.0 Hz, 1H), 7.95 (d, J=6.8 Hz, 2H), 7.79-7.74(m, 1H), 7.53-7.51 (m, 2H), 7.31-7.30 (m, 2H), 7.23-7.21 (m, 1H), 6.85(dd, J=2.8 Hz, 8.8 Hz, 1H), 4.52 (d, J=6.0 Hz, 2H), 3.92 (s, 3H), 2.25(s, 3H). MS (ESI+APCI; multimode): 385 [M+H]⁺:

Step-17: Synthesis of2-Chloro-N-(4-(3-fluoro-6-oxo-1,6-dihydropyridin-2-yl)benzyl)-6-methylbenzamide(Compound (1e)): Prepared as in Example 1 (Step-4 in Scheme 1). Theresidue was purified silica gel chromatography (10% MeOH in CH₂Cl₂) toafford2-chloro-N-(4-(3-fluoro-6-oxo-1,6-dihydropyridin-2-yl)benzyl)-6-methylbenzamide(1e) (70.0 mg, 47% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 10.9 (s, 1H), 9.06 (t, J=6.0 Hz, 1H), 7.81 (d, J=7.6 Hz,2H), 7.67-7.62 (m, 1H), 7.51-7.48 (m, 2H), 7.31-7.29 (m, 2H), 7.23-7.21(m, 1H), 6.60 (dd, J=2.8 Hz, 8.8 Hz, 1H), 4.51 (d, J=6.0 Hz, 2H), 2.24(s, 3H). MS (ESI+APCI; multimode): 371 [M+H]⁺: HPLC: 95.7 (% of AUC).

Example 6: Synthesis of2-Chloro-N-(4-(3-fluoro-6-oxo-1,6-dihydropyridin-2-yl)benzyl)benzamide(1f)

Compound (1f) was prepared via the synthesis summarized in Scheme 6(below).

Step-18: Synthesis of N-(4-Bromobenzyl)-2-chlorobenzamide (17): Preparedas in Example 5 (Step-14 in Scheme 5). The residue was purified bysilica gel chromatography (40% EtOAc in hexanes) to affordN-(4-N-(4-bromobenzyl)-2-chlorobenzamide (17) (2.50 g, 67% yield) as anoff white solid. ¹H NMR (400 MHz, DMSO-d₆): δ 8.99 (t, J=6.0 Hz, 1H),7.55-7.40 (m, 6H), 7.39-7.31 (m, 2H), 4.41 (d, J=6.0 Hz, 2H). MS(ESI+APCI; multimode): 324 [M+H]⁺

Step-19: Synthesis of2-Chloro-N-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)benzamide(18): Prepared as in Example 5 (Step-15 in Scheme 5). The residue waspurified by silica gel chromatography (60% EtOAc in hexanes) to afford2-chloro-N-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)benzamide(18) (500 mg, 43% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 8.99 (t, J=6.0 Hz, 1H), 7.65 (d, J=8.0 Hz, 2H), 7.51-7.36(m, 6H), 4.46 (d, J=6.0 Hz, 2H), 1.29 (s, 12H). MS (ESI+APCI;multimode): 372 [M+H]⁺

Step-20: Synthesis of2-Chloro-N-(4-(3-fluoro-6-methoxypyridin-2-yl)benzyl)benzamide 20):Prepared as in Example 5 (Step-16 in Scheme 5). The residue was purifiedby silica gel chromatography (50% EtOAc in hexanes) to afford2-chloro-N-(4-(3-fluoro-6-methoxypyridin-2-yl)benzyl)benzamide (20) (180mg, 60% yield) as an off white solid. ¹H NMR (400 MHz, DMSO-d₆): δ 9.06(t, J=5.6 Hz, 1H), 7.96-7.94 (m, 2H), 7.79-7.74 (m, 1H), 7.53-7.39 (m,6H), 6.85 (dd, J=2.8 Hz, 8.8 Hz, 1H), 4.51 (d, J=6.0 Hz, 2H), 3.92 (s,3H). MS (ESI+APCI; multimode): 371 [M+H]⁺:

Step-21: Synthesis of2-Chloro-N-(4-(3-fluoro-6-oxo-1,6-dihydropyridin-2-yl)benzyl)benzamide(Compound (1f)): Prepared as in Example 1 (Step-4 in Scheme 1). Theresidue was purified silica gel chromatography (10% MeOH in CH₂Cl₂) toafford2-chloro-N-(4-(3-fluoro-6-oxo-1,6-dihydropyridin-2-yl)benzyl)benzamide(1f) (20.0 mg, 16% yield) as an off white solid ¹H NMR (400 MHz,DMSO-d₆): δ 11.06 (brs, 1H), 9.03 (t, J=6.0 Hz, 1H), 7.81 (d, J=7.2 Hz,2H), 7.67-7.65 (m, 1H), 7.52-7.41 (m, 6H), 6.59 (dd, J=2.8 Hz, 8.8 Hz,1H), 4.50 (d, J=6.0 Hz, 2H). MS (ESI+APCI; multimode): 357 [M+H]⁺: HPLC:95.3 (% of AUC).

Example 7: Synthesis of4-Bromo-N-(4-(3-fluoro-6-oxo-1,6-dihydropyridin-2-yl)benzyl)-2-methylnicotinamide(1g)

Compound 1g was prepared via the synthesis summarized in Scheme 7(below).

Step-22: Synthesis of N-(4-Bromobenzyl)-4-chloro-2-methylnicotinamide(21): Prepared as in Example 5 (Step-14 in Scheme 5). The residue waspurified by silica gel chromatography (70% EtOAc in hexanes) to affordN-(4-bromobenzyl)-4-chloro-2-methylnicotinamide (21) (550 mg, 61% yield)as an off white solid. ¹H NMR (400 MHz, DMSO-d₆): δ 9.19 (t, J=6.0 Hz,1H), 8.42 (d, J=5.6 Hz, 1H), 7.57-7.54 (m, 2H), 7.44 (dd, J=0.8 Hz,J=5.6 Hz, 1H), 7.35-7.32 (m, 2H), 4.44 (d, J=6.0 Hz, 2H), 2.40 (s, 3H).MS (ESI+APCI; multimode): 339 [M+H]⁺.

Step-23: Synthesis of4-Chloro-2-methyl-N-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)nicotinamide(22): Prepared as in Example 5 (Step-15 in Scheme 5). The residue waspurified by silica gel chromatography (70% EtOAc in hexanes) to afford-4-chloro-2-methyl-N-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyl)nicotinamide(22) (200 mg, 58% yield) as a semi solid. ¹H NMR (400 MHz, DMSO-d₆): δ9.21 (t, J=6.0 Hz, 1H), 8.42 (d, J=5.6 Hz, 1H), 7.66 (d, J=8.0 Hz, 2H),7.44 (dd, J=0.4 Hz, J=5.2 Hz, 1H), 7.39 (d, J=8.0 Hz, 2H), 4.44 (d,J=6.0 Hz, 2H), 2.40 (s, 3H), 1.29 (s, 12H). MS (ESI+APCI; multimode):387 [M+H]⁺.

Step-24: Synthesis of4-Chloro-N-(4-(3-fluoro-6-methoxypyridin-2-yl)benzyl)-2-methylnicotinamide(23): Prepared as in Example 1 (Step-3 in Scheme 1). The residue waspurified by silica gel chromatography (80% EtOAc in hexanes) to afford-4-chloro-N-(4-(3-fluoro-6-methoxypyridin-2-yl)benzyl)-2-methylnicotinamide(23) (100 mg, 50% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 9.24 (t, J=6.0 Hz, 1H), 8.43 (d, J=5.6 Hz, 1H), 7.96 (dd,J=1.2 Hz, J=8.4 Hz, 2H), 7.79-7.74 (m, 2H), 7.52 (d, J=8.4 Hz, 2H), 7.45(dd, J=0.4 Hz, J=5.2 Hz, 1H), 6.86 (d, J=2.8 Hz, J=8.8 Hz, 2H), 4.55 (d,J=6.0 Hz, 2H), 3.92 (s, 3H), 2.5 (s, 3H). MS (ESI+APCI; multimode): 386[M+H]⁺.

Step-25:4-Bromo-N-(4-(3-fluoro-6-oxo-1,6-dihydropyridin-2-yl)benzyl)-2-methylnicotinamide(12): Prepared as in Example 1 (Step-4 in Scheme 1). The residue waspurified silica gel chromatography (12% MeOH in CH₂Cl₂) to afford2-bromo-N-(4-(3-fluoro-6-oxo-1,6-dihydropyridin-2-yl)benzyl)-2-methylnicotinamide(1g) (25.0 mg, 23% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 11.01 (brs, 1H), 9.22 (s, 1H), 8.32 (d, J=5.2 Hz, 1H), 7.82(d, J=7.2 Hz, 2H), 7.68-7.50 (m, 4H), 6.60 (d, J=7.2 Hz, 1H), 4.53 (d,J=5.6 Hz, 2H), 2.43 (s, 3H) MS (ESI+APCI; multimode): 416 [M+H]⁺: HPLC:96.8 (% of AUC).

Example 8: Synthesis of4-Chloro-N-(4-(3-fluoro-6-oxo-1,6-dihydropyridin-2-yl)benzyl)-2-methylnicotinamide(1h)

Compound 1h was prepared via the synthesis summarized in Scheme 8(below).

Step-26: Synthesis of4-Chloro-N-(4-(3-fluoro-6-oxo-1,6-dihydropyridin-2-yl)benzyl)-2-methylnicotinamide(1h): Prepared as in Example 3 (Step-8 in Scheme 3). The residue waspurified silica gel chromatography (10% MeOH in CH₂Cl₂) to afford4-chloro-N-(4-(3-fluoro-6-oxo-1,6-dihydropyridin-2-yl)benzyl)-2-methylnicotinamide(1h) (45.0 mg, 31% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 10.9 (brs, 1H), 9.22 (t, J=6.0 Hz, 1H), 8.42 (d, J=5.2 Hz,1H), 7.82 (d, J=7.6 Hz, 2H), 7.67-7.63 (m, 1H), 7.50-7.44 (m, 3H), 6.60(dd, J=6.8 Hz, 9.2 Hz, 1H), 4.53 (d, J=5.6 Hz, 2H), 2.43 (s, 3H). MS(ESI+APCI; multimode): 372 [M+H]⁺: HPLC: 95.8 (% of AUC).

Example 9: Synthesis of2,6-dichloro-N-((3′-fluoro-6′-oxo-1′,6′-dihydro-[2,2′-bipyridin]-5-yl)methyl)benzamide(1i)

Compound 1i was prepared via the synthesis summarized in Scheme 9(below).

Step-27: Synthesis of3′-Fluoro-6′-methoxy-[2,2′-bipyridine]-5-carbonitrile (25): Prepared asin Example 1 (Step-1 in Scheme 1). The residue was purified by silicagel chromatography (10% EtOAc in hexanes) to afford3′-fluoro-6′-methoxy-[2,2′-bipyridine]-5-carbonitrile (25) (120 mg, 15%yield) as an off white solid. ¹H NMR (400 MHz, DMSO-d₆): δ 9.14 (d,J=2.0 Hz, 1H), 8.47 (dd, J=2.4 Hz, J=8.4 Hz, 1H), 8.27 (d, J=8.4 Hz,1H), 7.88-7.83 (m, 1H), 7.06 (dd, J=2.8 Hz, J=8.8 Hz, 1H), 3.94 (s, 3H).MS (ESI+APCI; multimode): 230 [M+H]⁺:

Step-28: Synthesis of tert-Butyl((3′-fluoro-6′-methoxy-[2,2′-bipyridin]-5-yl)methyl)carbamate (26): To astirred solution of3′-fluoro-6′-methoxy-[2,2′-bipyridine]-5-carbonitrile (25) (120 mg, 0.52mmol) in MeOH:THF (1:3 ratio; 18 mL), were added NiCl₂·6H₂O (147 mg,0.62 mmol), (Boc)₂O (340 mg, 1.56 mmol) and NaBH₄ (59 mg, 1.56 mmol) at0° C. under N₂ atmosphere. The reaction mixture was stirred at roomtemperature for 12 h. The residue was diluted with water and extractedwith EtOAc (2×50 mL). The organic extract was separated, washed withwater, brine (1×50 mL) and dried over Na₂SO₄. After evaporation of thesolvent, the residue was purified by silica-gel chromatography (20%EtOAc in hexanes) to afford tert-butyl((3′-fluoro-6′-methoxy-[2,2′-bipyridin]-5-yl)methyl)carbamate (26) (120mg, 44% yield) as an off-white solid. ¹H NMR (400 MHz, DMSO-d₆): δ 8.55(d, J=1.6 Hz, 1H), 7.98 (d, J=8.0 Hz, 1H), 7.81-7.77 (m, 2H), 7.51 (t,J=5.2 Hz, 1H), 6.95-6.92 (m, 1H), 4.21 (d, J=6.0 Hz, 2H), 3.91 (s, 3H),1.40 (s, 9H). MS (ESI+APCI; multimode): 334 [M+H]⁺

Step-29: Synthesis of(3′-fluoro-6′-methoxy-[2,2′-bipyridin]-5-yl)methanamine hydrochloride(27): To a stirred solution of tert-butyl((3′-fluoro-6′-methoxy-[2,2′-bipyridin]-5-yl)methyl)carbamate (26) (80.0mg, 0.24 mmol), in 2,2,2-trifluoroethanol (1.0 mL) was added TMSCl (80.0mg, 0.720 mmol) at room temperature under N₂ atmosphere. The reactionmixture was stirred at room temperature for 12 h. The solvent wasremoved under reduced pressure and MTBE added. The solids were filteredand washed with MTBE to afford(3′-fluoro-6′-methoxy-[2,2′-bipyridin]-5-yl)methanamine hydrochloride(27) (50.0 mg, 89% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 8.78 (s, 1H), 8.41 (brs, 2H), 8.10 (d, J=1.20 Hz, 2H),7.84-7.80 (m, 1H), 6.99 (dd, J=2.8 Hz, J=8.8 Hz, 1H), 4.16 (d, J=5.6 Hz,2H), 3.92 (s, 3H).

Step-30: Synthesis of2,6-Dichloro-N-((3′-fluoro-6′-methoxy-[2,2′-bipyridin]-5-yl)methyl)benzamide(28): Prepared as in Example 1 (Step-3 in Scheme 1). The residue waspurified by silica gel chromatography (50% EtOAc in hexanes) to afford-2,6-dichloro-N-((3′-fluoro-6′-methoxy-[2,2′-bipyridin]-5-yl)methyl)benzamide(28) (40.0 mg, 53% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 9.33 (t, J=5.6 Hz, 1H), 8.70 (d, J=1.6 Hz, 1H), 7.95 (dd,J=2.4 Hz, J=8.4 Hz, 1H), 7.81-7.77 (m, 1H), 7.53 (dd, J=1.6 Hz, J=8.8Hz, 2H), 7.47-7.43 (m, 1H), 6.95 (dd, J=2.8 Hz, J=8.8 Hz, 1H), 4.57 (d,J=5.6 Hz, 2H), 3.92 (s, 3H). MS (ESI+APCI; multimode): 406 [M+H]⁺.

Step-31: Synthesis of2,6-Dichloro-N-((3′-fluoro-6′-oxo-1′,6′-dihydro-[2,2′-bipyridin]-5-yl)methyl)benzamide(1i): Prepared as in Example 1 (Step-4 in Scheme 1). The residue waspurified silica gel chromatography (7% MeOH in CH₂Cl₂) to afford2,6-dichloro-N-((3′-fluoro-6′-oxo-1′,6′-dihydro-[2,2′-bipyridin]-5-yl)methyl)benzamide(1i) (25.0 mg, 65% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 11.00 (brs, 1H), 9.32 (t, J=6.0 Hz, 1H), 8.71 (s, 1H),7.96-7.89 (m, 2H), 7.69 (t, J=9.6 Hz, 1H), 7.54-7.43 (m, 3H), 6.64 (t,J=2.8 Hz, 1H), 4.57 (d, J=5.6 Hz, 2H). MS (ESI+APCI; multimode): 392[M+H]⁺: HPLC: 98.0 (% of AUC).

Example 10: Synthesis of2,6-Dichloro-N-((6′-oxo-1′,6′-dihydro-[2,2′-bipyridin]-5-yl)methyl)benzamide(1j)

Compound 1j was prepared via the synthesis summarized in Scheme 10(below).

Step-32: Synthesis of tert-Butyl ((6-chloropyridin-3-yl)methyl)carbamate(30): To a stirred solution of (6-chloropyridin-3-yl)methanamine (29)(300 mg, 2.11 mmol) in CH₂Cl₂ (5.0 mL), were added Et₃N (0.94 mL, 6.34mmol) and Boc-anhydride (0.58 mL, 2.53 mmol) at 0° C. under N₂atmosphere. The reaction mixture was stirred at room temperature for 16h. The residue was diluted with water and extracted with EtOAc (2×50mL). The organic extract was separated, washed with water, brine (1×50mL) and dried over Na₂SO₄. After evaporation of the solvent, the residuewas purified by silica-gel chromatography (20% EtOAc in hexanes) toafford tert-butyl ((6-chloropyridin-3-yl)methyl)carbamate (30) (305 mg,60% yield) as an off white solid. ¹H NMR (400 MHz, DMSO-d₆): δ 8.26 (s,1H), 7.72-7.69 (m, 1H), 7.48 (d, J=8.0 Hz, 2H), 4.14 (d, J=6.0 Hz, 2H),1.38 (s, 9H).

Step-33: Synthesis of tert-Butyl((6′-methoxy-[2,2′-bipyridin]-5-yl)methyl)carbamate (31): Prepared as inExample 1 (Step-1 in Scheme 1). The residue was purified silica gelchromatography (10% EtOAc in hexanes) to afford tert-butyl((6′-methoxy-[2,2′-bipyridin]-5-yl)methyl)carbamate (31) (1.40 g, 54%yield) as an off white solid. ¹H NMR (400 MHz, DMSO-d₆): δ 8.53 (d,J=2.0, 1H), 8.33 (d, J=8.0 Hz, 1H), 7.97 (d, J=7.6 Hz, 1H), 7.85-7.52(m, 3H), 6.85 (d, J=8.4 Hz, 1H), 4.20 (d, J=6.0 Hz, 1H), 3.98 (s, 3H),1.40 (s, 9H). MS (ESI+APCI; multimode): 316.0 [M+H]⁺.

Step-34: Synthesis of (6′-methoxy-[2,2′-bipyridin]-5-yl)methanaminehydrochloride (33): Prepared as in Example 9 (Step-29 in Scheme 9). Thesolvent was removed under reduced pressure and MTBE added. The solidswere filtered and washed with MTBE to afford6′-methoxy-[2,2′-bipyridin]-5-yl)methanamine hydrochloride (33) ((680mg, 77% yield) as an off white solid. ¹H NMR (400 MHz, DMSO-d₆): δ 8.77(s, 1H), 8.46-7.85 (m 7H), 6.93-6.91 (m, 1H), 4.15 (d, J=6.0 Hz, 2H),3.99 (s, 3H).

Step-35: Synthesis of2,6-Dichloro-N-((6′-methoxy-[2,2′-bipyridin]-5-yl)methyl)benzamide 33):Prepared as in Example 1 (Step-3 in Scheme 1). The residue was purifiedsilica gel chromatography (50% EtOAc in hexanes) to afford6-dichloro-N-((6′-methoxy-[2,2′-bipyridin]-5-yl)methyl)benzamide (33):160 mg, 52% yield) as an off white solid. ¹H NMR (400 MHz, DMSO-d₆): δ9.32 (t, J=6.0 Hz, 1H), 8.68 (s, 1H), 8.37 (d, J=8.0 Hz, 1H), 7.99-7.82(m, 3H), 7.54-7.43 (m, 3H), 6.88 (d, J=8.0 Hz, 1H), 4.56 (d, J=6.0 Hz,2H), 3.98 (s, 3H). MS (ESI+APCI; multimode): 387.9 [M+1]⁺. HPLC: 97.2 (%of AUC).

Step-36: Synthesis of2,6-Dichloro-N-((6′-oxo-1′,6′-dihydro-[2,2′-bipyridin]-5-yl)methyl)benzamide(1i): Prepared as in Example 1 (Step-4 in Scheme 1). The residue waspurified silica gel chromatography (15% MeOH in CH₂Cl₂) to afford2,6-dichloro-N-((6′-oxo-1′,6′-dihydro-[2,2′-bipyridin]-5-yl)methyl)benzamide(1j) (58.0 mg, 60% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 11.01 (brs, 1H), 9.32 (t, J=6.0 Hz, 1H), 8.70 (s, 1H), 8.14(d, J=8.4 Hz, 1H), 7.95-7.43 (m, 5H), 7.20 (s, 1H), 6.550 (d, J=8.8 Hz,1H), 4.57 (d, J=6.0 Hz, 2H). MS (ESI+APCI; multimode): 373.9 [M+NH₄]⁺.HPLC: 98.2 (% of AUC).

Example 11: Synthesis of2-Chloro-6-methyl-N-((6′-oxo-1′,6′-dihydro-[2,2′-bipyridin]-5-yl)methyl)benzamide(1k)

Compound 1k was prepared via the synthesis summarized in Scheme 11(below).

Step-37: Synthesis of2-Chloro-N-((6′-methoxy-[2,2′-bipyridin]-5-yl)methyl)-6-methylbenzamide(33): Prepared as in Example 1 (Step-3 in Scheme 1). The residue waspurified silica gel chromatography (50% EtOAc in hexanes) to afford2-chloro-N-((6′-methoxy-[2,2′-bipyridin]-5-yl)methyl)-6-methylbenzamid(33) (150 mg, 54% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 9.12 (t, J=6.0 Hz, 1H), 8.67 (s, 1H), 8.37 (d, J=8.0 Hz,1H), 7.99-7.82 (m, 3H), 7.32-7.21 (m, 3H), 6.87 (d, J=8.0 Hz, 1H), 4.54(d, J=6.0 Hz, 2H), 3.98 (s, 3H), 2.23 (s, 3H). MS (ESI+APCI; multimode):368.0 [M+1]⁺. HPLC: 95.6 (% of AUC).

Step-38: Synthesis of2-Chloro-6-methyl-N-((6′-oxo-1′,6′-dihydro-[2,2′-bipyridin]-5-yl)methyl)benzamide(1k): Prepared as in Example 1 (Step-4 in Scheme 1). The residue waspurified silica gel chromatography (15% MeOH in CH₂Cl₂) to afford2-chloro-6-methyl-N-((6′-oxo-1′,6′-dihydro-[2,2′-bipyridin]-5-yl)methyl)benzamide(1k) (58.0 mg, 60% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 11.01 (brs, 1H), 9.32 (t, J=6.0 Hz, 1H), 8.70 (s, 1H), 8.14(d, J=8.4 Hz, 1H), 7.95-7.43 (m, 5H), 7.20 (s, 1H), 6.550 (d, J=8.8 Hz,1H), 4.57 (d, J=6.0 Hz, 2H). MS (ESI+APCI; multimode): 373.9 [M+NH₄]⁺.HPLC: 98.2 (% of AUC).

Example 12: Synthesis of2-chloro-N-((6′-oxo-1′,6′-dihydro-[2,2′-bipyridin]-5-yl)methyl)benzamide(1l)

Compound 1l was prepared via the synthesis summarized in Scheme 12(below).

Step-39: Synthesis of2-Chloro-N-((6′-methoxy-[2,2′-bipyridin]-5-yl)methyl)benzamide 34):Prepared as in Example 1 (Step-3 in Scheme 1). The residue was purifiedsilica gel chromatography (50% EtOAc in hexanes) to afford2-chloro-N-((6′-methoxy-[2,2′-bipyridin]-5-yl)methyl)benzamide (34) (170mg, 61% yield) as an off white solid. ¹H NMR (400 MHz, DMSO-d₆): δ 9.14(t, J=6.0 Hz, 1H), 8.66 (s, 1H), 8.37 (d, J=8.0 Hz, 1H), 7.99-7.82 (m,3H), 7.53-7.39 (m, 4H), 6.88 (d, J=8.0 Hz, 1H), 4.54 (d, J=6.0 Hz, 2H),3.98 (s, 3H). MS (ESI+APCI; multimode): 354.0 [M+1]⁺. HPLC: 97.3 (% ofAUC).

Step-40: Synthesis of2-Chloro-N-((6′-oxo-1′,6′-dihydro-[2,2′-bipyridin]-5-yl)methyl)benzamide(1l): Prepared as in Example 1 (Step-4 in Scheme 1). The residue waspurified silica gel chromatography (15% MeOH in CH₂Cl₂) to2-chloro-N-((6′-oxo-1′,6′-dihydro-[2,2′-bipyridin]-5-yl)methyl)benzamide(1l) (65.0 mg, 68% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 11.05 (s, 1H), 9.12 (t, J=6.0 Hz, 1H), 8.68 (s, 1H), 8.14(d, J=8.4 Hz, 1H), 7.93 (d, J=8.4 Hz, 1H), 7.63-7.39 (m, 5H), 7.39 (s,1H), 6.50 (d, J=8.8 Hz, 1H), 4.54 (d, J=6.0 Hz, 2H). MS (ESI+APCI;multimode): 340.0 [M+1]⁺. HPLC: 99.9 (% of AUC).

Example 13: Synthesis of4-Chloro-2-methyl-N-((6′-oxo-1′,6′-dihydro-[2,2′-bipyridin]-5-yl)methyl)nicotinamide(1m)

Compound 1m was prepared via the synthesis summarized in Scheme 13(below).

Step-41: Synthesis of4-Chloro-N-((6′-methoxy-[2,2′-bipyridin]-5-yl)methyl)-2-methylnicotinamide(33): Prepared as in Example 1 (Step-3 in Scheme 1). The residue waspurified by silica gel chromatography (10% MeOH in CH₂Cl₂) to afford4-chloro-N-((6′-methoxy-[2,2′-bipyridin]-5-yl)methyl)-2-methylnicotinamide(33) (170 mg, 46% yield) as an off-white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 9.28 (t, J=6.0 Hz, 1H), 8.67 (d, J=1.6 Hz, 1H), 8.43 (d,J=5.6 Hz, 1H), 8.37 (d, J=8.0 Hz, 1H), 7.98 (dd, J=0.8 Hz, J=7.6 Hz,1H), 7.93 (dd, J=2.4, Hz, J=8.4 Hz, 1H), 7.84 (t, J=0.8 Hz, 1H), 7.45(d, J=5.2 Hz, 1H), 6.88 (dd, J=0.8, Hz, J=8.0 Hz, 1H), 4.57 (d, J=6.0Hz, 2H), 3.98 (s, 3H), 2.42 (s, 3H); MS (ESI+APCI; multimode): 369[M+H]⁺; HPLC: 96.7 (% of AUC).

Step-45: Synthesis of4-Chloro-2-methyl-N-((6′-oxo-1′,6′-dihydro-[2,2′-bipyridin]-5-yl)methyl) nicotinamide (1m): Prepared as in Example 1 (Step-4 in Scheme1). The residue was purified silica gel chromatography (16% MeOH inCH₂Cl₂) to4-chloro-2-methyl-N-((6′-oxo-1′,6′-dihydro-[2,2′-bipyridin]-5-yl)methyl) nicotinamide (1m) (70.0 mg, 56% yield) as an off-white solid. ¹HNMR (400 MHz, DMSO-d₆): δ 11.07 (s, 1H), 9.31 (t, J=5.2 Hz, 1H), 8.69(S, 1H), 8.44 (d, J=5.6 Hz, 1H), 8.16 (d, J=8.0 Hz, 1H), 7.94 (d, J=8.0Hz, 1H), 7.62-7.60 (m, 1H), 7.46 (d, J=5.6 Hz, 1H), 7.19-7.10 (m, 1H),6.50 (brs, 1H), 4.57 (d, J=5.6 Hz, 2H), 2.41 (s, 3H): MS (ESI+APCI;multimode): 355 [M+H]⁺: HPLC: >99 (% of AUC).

Example 14: Synthesis of2-Chloro-6-methyl-N-((2-(6-oxo-1,6-dihydropyridin-2-yl)pyrimidin-5-yl)methyl)benzamide(1n)

Compound 1n was prepared via the synthesis summarized in Scheme 14(below).

Step-43: Synthesis of 2-(6-Methoxypyridin-2-yl)pyrimidine-5-carbonitrile(35): To a degassed solution of 2-chloropyrimidine-5-carbonitrile (34)(1.00 g, 7.24 mmol) in 1,4 dioxane:water (4:1) (36 mL), were added2-methoxy-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine (I)(2.2 g, 9.42 mmol), Cs₂CO₃ (7.06 g, 21.7 mmol) and Pd(dppf)Cl₂·CH₂Cl₂(591 mg, 0.72 mmol) at room temperature. The mixture was again de-gassedwith Ar (g) for 5 min and heated at 100° C. for 5 h. The residue wasdiluted with water and extracted with EtOAc (2×100 mL). The organicextract was separated, washed with water, brine (1×100 mL) and driedover Na₂SO₄. After evaporation of the solvent, the residue was purifiedby silica-gel chromatography (50% EtOAc in hexanes) to afford2-(6-methoxypyridin-2-yl)pyrimidine-5-carbonitrile (35) (600 mg, 40%yield) as an off-white solid. ¹H NMR (400 MHz, DMSO-d₆): δ 9.44 (s, 2H),8.17-8.09 (m, 1H), 7.98-7.90 (m, 1H), 7.06 (dd, J=8.3 Hz, J=8.3 Hz, 1H),3.97 (s, 3H); MS (ESI+APCI; multimode): 213 [M+H]⁺.

Step-44: Synthesis of(2-(6-methoxypyridin-2-yl)pyrimidin-5-yl)methanamine (36): To a stirredsolution of 2-(6-methoxypyridin-2-yl)pyrimidine-5-carbonitrile (35) (400mg, 1.88 mmol), in EtOH (40 mL), was added Raney-Ni (837 mg, 9.43 mmol)and NH₄OH (30 mL) under inert atmosphere. The mixture was stirred atroom temperature under Hydrogen atmosphere for 2 h. The reaction mixturewas filtered through celite, filtrate was concentrated under reducedpressure. The residue was purified by silica-gel chromatography toafford (16% (10% NH4OH in MeOH) in CH₂Cl₂) to afford(2-(6-methoxypyridin-2-yl)pyrimidin-5-yl)methanamine (36) (280 mg, 68%yield) as an off white solid. ¹H NMR (400 MHz, DMSO-d₆): δ 8.89 (s, 2H),7.98 (dd, J=0.8 Hz, J=7.2 Hz, 1H), 7.88-7.84 (m, 1H), 6.94 (dd, J=0.8Hz, J=8.0 Hz, 1H), 3.96 (s, 3H), 3.81 (s, 2H): MS (ESI+APCI; multimode):217 [M+H]⁺.

Step-45: Synthesis of2-Chloro-N-((2-(6-methoxypyridin-2-yl)pyrimidin-5-yl)methyl)-6-methylbenzamide(37): Prepared as in Example 1 (Step-3 in Scheme 1). The residue waspurified by silica gel chromatography (10% MeOH in CH₂Cl₂) to afford2-chloro-N-((2-(6-methoxypyridin-2-yl)pyrimidin-5-yl)methyl)-6-methylbenzamide(37) (270 mg, 61% yield) as off-white solid. ¹H NMR (400 MHz, DMSO-d₆):δ 9.17 (t, J=5.6 Hz, 1H), 8.95 (s, 2H), 8.01 (dd, J=0.4 Hz, J=7.2 Hz,1H), 7.89-7.85 (m, 1H), 7.32-7.29 (m, 2H), 7.24-7.22 (m, 1H), 6.97 (dd,J=0.8 Hz, J=8.4 Hz, 1H), 4.55 (d, J=5.6 Hz, 2H), 3.96 (s, 3H), 2.23 (s,3H): MS (ESI+APCI; multimode): 369 [M+H]⁺: HPLC: >99 (% of AUC).

Step-46: Synthesis of2-Chloro-6-methyl-N-((2-(6-oxo-1,6-dihydropyridin-2-yl)pyrimidin-5-yl)methyl)benzamide(1n): Prepared as in Example 1 (Step-4 in Scheme 1). The residue waspurified silica gel chromatography (16% MeOH in CH₂Cl₂) to2-chloro-6-methyl-N-((2-(6-oxo-1,6-dihydropyridin-2-yl)pyrimidin-5-yl)methyl)benzamide(1n) (90.0 mg, 59% yield) as an off white solid. ¹H NMR (400 MHz,DMSO-d₆): δ 10.99 (brs, 1H), 9.20 (t, J=6.0 Hz, 1H), 8.95 (S, 2H),7.64-7.60 (m, 1H), 7.32-7.28 (m, 3H), 7.25-7.22 (m, 1H), 6.57 (dd, J=0.4Hz, J=9.2 Hz, 1H), 4.56 (d, J=6.0 Hz, 2H), 2.22 (s, 3H): MS (ESI+APCI;multimode): 355 [M+H]⁺: HPLC: 95.6 (% of AUC).

Example 15: ALDH-1, ALDH-2, ALDH-3, MAO-A, MAO-B and HepaRG SpheroidAssays of ALDH-2 Inhibitor Compounds

This example illustrates studies of the exemplary ALDH-2 inhibitorcompounds of the present disclosure in assays measuring inhibition ofALDH-2, ALDH-1, ALDH-3, as well as MAO-A, and MAO-B. The example alsoillustrates studies of the compounds in HepaRG 3D spheroid assay thatprovides a measure of potential hepatotoxic liability.

Materials and Methods

A. ALDH-2 inhibition assay: The ALDH-2 reaction mixture used in theassay contained 125 μM formaldehyde, 75 μM NAD+, 20 mM NaCl, 10 mMMgCl₂, and 20 nM recombinant human ALDH-2 in 50 mM Hepes buffer, pH 7.5in a final volume of 10 μL using 384-well Corning 3820 plates. After 60min of pre-incubation of the test ALDH-2 inhibitor compound with ALDH-2,the reaction was started by adding NAD+ and formaldehyde and the assayreaction mixture was allowed to proceed for 60 minutes. Activity of theALDH-2 enzyme was determined by monitoring NADH formation usingPerkin-Elmer Envision Reader with excitation and emission wavelengthsset at 340 and 460 nm, respectively. Inhibition was determined as IC₅₀,which refers to the concentration of the test ALDH-2 inhibitor compoundthat inhibited the reaction by 50%.

B. ALDH-1 inhibition assay: The ALDH-1 reaction mixture used in theassay contained 100 μM formaldehyde, 2.5 mM NAD+, 20 mM NaCl, 10 mMMgCl₂, 1 mM dithiothreitol (DTT; reducing agent), and 50 nM recombinanthuman ALDH-1 in 50 mM Hepes buffer, pH 7.5 in a final volume of 10 μLusing 384-well Corning 3820 plates. After 60 min of pre-incubation ofthe test ALDH-2 inhibitor compound with ALDH-1, the reaction was startedby adding NAD+ and formaldehyde and the assay reaction mixture wasallowed to proceed for 60 minutes. Activity of the ALDH-1 enzyme wasdetermined by monitoring NADH formation using Perkin-Elmer EnvisionReader with excitation and emission wavelengths set at 340 and 460 nm,respectively. Inhibition was determined as IC₅₀, which refers to theconcentration of the test ALDH-2 inhibitor compound that inhibited thereaction by 50%.

C. ALDH-3 inhibition assay: The ALDH-3 reaction mixture used in theassay contained 200 μM benzaldehyde, 2.5 mM NAD+, 20 mM NaCl, 10 mMMgCl₂, and 10 nM recombinant human ALDH-3 in 50 mM Hepes buffer, pH 7.5in a final volume of 10 μL using 384-well Corning 3820 plates. After 60min of pre-incubation of the test ALDH-2 inhibitor compound with ALDH-3,the reaction was started by adding NAD+ and benzaldehyde and the assayreaction mixture was allowed to proceed for 60 minutes. Activity of theALDH-3 enzyme was determined by monitoring NADH formation usingPerkin-Elmer Envision Reader with excitation and emission wavelengthsset at 340 and 460 nm, respectively. Inhibition was determined as IC₅₀,which refers to the concentration of the test ALDH-2 inhibitor compoundthat inhibited the reaction by 50%.

D. MAO-A and MAO-B inhibition assays: MAO assays included luminogenicMAO substrate, reaction buffers, Luciferin Detection, and areconstitution buffer with esterase. The MAO reaction mixture used inthe assay included microsome contained MAO-A (2 μg) or MAO-B (10 μg),160 μM substrate for MAO-A or 16 μM substrate for MAO-B, MAO-A buffer(100 mM Hepes buffer, pH 7.5, 5% glycerol) or MAO-B buffer (100 mMHepes, pH 7.5, 5% glycerol, 10% dimethyl sulfoxide) in a final volume of30 μL. After 20 minutes of pre-incubation of the MAO-A or MAO-B enzymewith the test ALDH-2 inhibitor compound, the reaction was initiated byadding enzyme substrate and the 60 reaction was allowed to proceed for60 minutes. Reconstituted Luciferin Detection Reagent (30 μL) was thenadded is added to simultaneously stop the MAO reaction and convert themethyl ester derivative to luciferin and produce light. The amount oflight produced is directly proportional to the activity of MAO. Themixtures were further incubated for 20 minutes and activity of theenzyme was determined using Perkin-Elmer Envision Reader. Inhibition wasdetermined as IC₅₀, which refers to the concentration of the test ALDH-2inhibitor compound that inhibited the reaction by 50%.

E. HepaRG® 3D spheroid assay: The HepaRG 3D spheroid assay is describedin Walker et al., “The evolution of strategies to minimise the risk ofhuman drug-induced liver injury (DILI) in drug discovery anddevelopment,” (2020) Archives of Toxicology, Vol. 94: 2559-2585.Briefly, HepaRG® cells were seeded into ultra-low adhesion 96-well blackwalled clear bottomed spheroid microplates. Following formation, thespheroids were dosed with test ALDH-2 inhibitor compound at a range ofconcentrations to yield an 8 point dose response curve with topconcentration at 100 mM (3 replicates per concentration) at days 1, 4, 7and 10 and 13. At the end of the incubation period, the spheroids wereloaded with the relevant dye/antibody for each cell health marker(spheroid count, spheroid size, DNA structure, mitochondrial mass,mitochondrial membrane potential, oxidative stress, glutathione content,and cellular ATP). The plates were then scanned using an automatedfluorescent cellular imager, ArrayScan® (Thermo Scientific Cellomics).The minimum effective concentration (“MEC”) was determined as the amountof the tested compound that significantly crosses vehicle controlthreshold of cell health marker.

Results

The results of the ALDH-2, ALDH-1, ALDH-3, MAO-A, MAO-B, and HepaRG 3Dspheroid assays for the exemplary ALDH-2 inhibitor compounds of Table 1are summarized in Table 3 below.

TABLE 3 Enzymatic Assays* HepaRG 3D Ratio IC₅₀ (μM) Spheroid** MEC toCompound ALDH2 ALDH-1 ALDH-3 MAO-A MAO-B MEC (μM) ALDH2 (1a)0.078 >10 >10 >10 >10 10.4 133 (1b) 0.137 >10 >10 >10 >10 No Effect >730(1c) 0.128 >10 >10 >10 >10 11.5 90 (1d) 0.027 >10 >10 >10 >10 NoEffect >3704 (1e) 0.009 >10 >10 >10 >10 50.4 5600 (1f)0.329 >10 >10 >10 >10 ND ND (1g) 0.028 >10 >10 >10 >10 46.7 1668 (1h)0.100 >10 >10 >10 >10 53.9 518 (1i) 0.004 >10 >10 >10 >10 15.3 3712 (1j)0.007 >10 >10 >10 >10 5.06 723 (1k) 0.010 >10 >10 >10 >10 21.0 2100 (1l)0.118 >10 >10 >10 >10 5.95 50 (1m) 0.980 >10 >10 >10 >10 ND ND (1n)0.031 >10 >10 >10 >10 7.48 245 *10 μM = highest concentration tested**100 μM = highest concentration tested, ND = not determined

Example 16: Formulation of Pharmaceutical Compositions

This example illustrates formulations of the pharmaceutical compositionscomprising ALDH-2 inhibitors of structural Formula (I) and Formula (II)that can be used in the methods of the present disclosure for treatingaddiction to a substance or condition of addiction or abuse.

Hard gelatin capsules: The ingredients listed below are mixed and filledinto hard gelatin capsules:

Quantity Ingredient (mg/capsule) Active Ingredient 30.0 Starch 305.0Magnesium stearate 5.0

240 mg Tablets: The ingredients listed below are blended and compressedto form 240 mg tablets:

Quantity Ingredient (mg/tablet) Active Ingredient 25.0 Cellulose,microcrystalline 200.0 Colloidal silicon dioxide 10.0 Stearic acid 5.0

120 mg Tablets: The ingredients listed below are blended and compressedas described below to form 120 mg tablets:

Quantity Ingredient (mg/tablet) Active Ingredient 30.0 mg Starch 45.0 mgMicrocrystalline cellulose 35.0 mg Polyvinylpyrrolidone  4.0 mg (as 10%solution in sterile water) Sodium carboxymethyl starch  4.5 mg Magnesiumstearate  0.5 mg Talc  1.0 mg Total  120 mg

The active ingredient, starch, and cellulose are passed through a No. 20mesh U.S. sieve and mixed thoroughly. The solution ofpolyvinylpyrrolidone is mixed with the resultant powders, which are thenpassed through a 16 mesh U.S. sieve. The granules so produced are driedat 50° C. to 60° C. and passed through a 16 mesh U.S. sieve. The sodiumcarboxymethyl starch, magnesium stearate, and talc, previously passedthrough a No. 30 mesh U.S. sieve, are then added to the granules which,after mixing, are compressed on a tablet machine to yield tablets eachweighing 120 mg.

Suppositories: Suppositories each containing 25 mg of active ingredient,are made as follows:

Ingredient Quantity Active Ingredient   25 mg Saturated fatty acidglycerides to 2,000 mg

The active ingredient is passed through a No. 60 mesh U.S. sieve andsuspended in the saturated fatty acid glycerides previously melted usingthe minimum heat necessary. The mixture is then poured into asuppository mold of nominal 2.0 g capacity and allowed to cool.

Suspensions: A suspension containing 50 mg of active ingredient per 5.0mL dose, is made as follows:

Ingredient Amount Active Ingredient 50.0 mg Xanthan gum  4.0 mg Sodiumcarboxymethyl cellulose (11%) Microcrystalline cellulose (89%) 50.0 mgSucrose 1.75 g Sodium benzoate 10.0 mg Flavor and Color q.v. Purifiedwater to  5.0 mL

The active ingredient, sucrose and xanthan gum are blended, passedthrough a No. 10 mesh U.S. sieve, and then mixed with a previously madesolution of the microcrystalline cellulose and sodium carboxymethylcellulose in water. The sodium benzoate, flavor, and color are dilutedwith some of the water and added with stirring. Sufficient water is thenadded to produce the required volume.

Subcutaneous: a subcutaneous formulation is prepared as follows:

Ingredient Quantity Active Ingredient 5.0 mg Corn Oil 1.0 mL

Injectable: an injectable formulation is prepared by combining thefollowing ingredients:

Ingredient Quantity Active ingredient 2.0 mg/mL Mannitol, USP  50 mg/mLGluconic acid, USP q.s. (pH 5-6) Water (distilled, sterile) q.s. to 1.0mL Nitrogen Gas, NF q.s.

Topical: a topical preparation is prepared by combining the followingingredients as described below:

Quantity Ingredients (g) Active ingredient 0.01-1 Span 60 2.0 Tween 602.0 Mineral oil 5.0 Petrolatum 0.10 Methyl paraben 0.15 Propyl paraben0.05 BHA (butylated hydroxy anisole) 0.01 Water q.s. to 100

All of the above ingredients, except water, are combined and heated to60° C. with stirring. A sufficient quantity of water at 60° C. is thenadded with vigorous stirring to emulsify the ingredients, and water thenadded q.s. 100 g.

All publications, patents, patent applications and other documents citedin this application are hereby incorporated by reference in theirentireties for all purposes to the same extent as if each individualpublication, patent, patent application or other document wereindividually indicated to be incorporated by reference for all purposes.

While various specific embodiments have been illustrated and described,it will be appreciated that various changes can be made withoutdeparting from the spirit and scope of the inventions.

What is claimed is:
 1. A compound of Formula (I):

wherein: X¹ is N or CR³, X² is N or CR⁴, X³ is N or CR⁶, with theprovisos that no more than one of X¹, X², and X³ is N; each of X⁴, andX⁵ is independently N or CR¹⁰; R¹¹ is H, halogen, optionally substitutedC₁₋₆ alkyl, or cycloalkyl; R⁷ is H, or optionally substituted C₁₋₆alkyl; each of R², R³, R⁴, R⁵, R⁶, R⁸, R⁹, and R¹⁰ is independently H,halogen, —CF₃, —OH, —CH₂OH, —CN, optionally substituted alkyl,optionally substituted alkylene, optionally substituted alkynyl,optionally substituted alkoxy, optionally substituted cycloalkyl,optionally substituted aryl, optionally substituted aralkyl, optionallysubstituted heteroaryl, optionally substituted heteroaralkyl, optionallysubstituted heterocyclyl, aminocarbonyl, acyl, acylamino, —O—(C₁ toC₆-alkyl)-O—(C₁ to C₆-alkyl), —CH₂OP(O)(OR²⁰)(OR²¹), —SO₂NR²⁴R²⁵; or—NR²⁴R²⁵, with the proviso that R² and R⁶ are not both Cl when X¹ isCR³, X² is CR⁴, X³ is CR⁶, X⁴ is CR¹⁰, X⁵ are CR¹⁰, and R¹¹ is H; eachof R²⁰ and R²¹ is independently Na⁺, Li⁺, K⁺, hydrogen, C₁₋₆ alkyl; orR²⁰ and R²¹ can be combined to represent a single divalent cation Zn²⁺,Ca²⁺, or Mg²⁺; and each of R²⁴ and R²⁵ is independently chosen fromhydrogen or C₁₋₆ alkyl or when combined together with the nitrogen towhich they are attached form a heterocycle; or a pharmaceuticallyacceptable salt, ester, single stereoisomer, mixture of stereoisomers,or a tautomer thereof.
 2. The compound of claim 1, wherein: (a) X¹ isCR³, X² is CR⁴, and X³ is CR⁶; (b) X¹ is N, X² is CR⁴, and X³ is CR⁶;(c) X¹ is CR³, X² is N, and X³ is CR⁶; or (d) X¹ is CR³, X² is CR⁴, andX³ is N.
 3. The compound of claim 1, wherein (a) X⁴ is CR¹⁰, and X⁵ isCR¹⁰; (b) X⁴ is CR¹⁰, and X⁵ is N; or (c) X⁴ is N, and X⁵ is N.
 4. Thecompound of claim 1, wherein each of R², R³, R⁴, R⁵, R⁷, R⁸, R⁹, R¹⁰,and R¹¹ are H.
 5. The compound of claim 1, wherein: (a) R² is selectedfrom H, Cl, F, or CH₃; (b) R³ is selected from H, Cl, F, and CH₃; (c) R⁵is selected from H, Cl, F, and CH₃; (d) R⁶ is selected from H, Cl, F,and CF₃; and/or (e) R¹¹ is selected from H and halogen; optionally,wherein R¹¹ is a 3-fluoro.
 6. The compound of claim 1, wherein thecompound is selected from compounds (1a), (1b), (1c), (1d), (1e), (1f),(1g), (1h), (1i), (1j), (1k), (1l), (1m), and (1n), or apharmaceutically acceptable salt, an ester, a single stereoisomer, amixture of stereoisomers, or a tautomer thereof


7. A compound of structural Formula (II):

wherein, each of X² and X³ are independently N or CH; R¹¹ is H, halogen,optionally substituted C₁₋₆ alkyl, or cycloalkyl; R¹ is selected from

each of R², and R⁶, is independently H, Br, Cl, F, CH₃, or CF₃; and eachof R³, R⁴, and R⁵, is independently H, Br, Cl, F, CH₃, CF₃, —OH, —CH₂OH,—CN, optionally substituted alkyl, optionally substituted alkylene,optionally substituted alkynyl, optionally substituted alkoxy,optionally substituted cycloalkyl, optionally substituted aryl,optionally substituted aralkyl, optionally substituted heteroaryl,optionally substituted heteroaralkyl, optionally substitutedheterocyclyl, aminocarbonyl, acyl, acylamino, —O—(C₁ to C₆-alkyl)-O—(C₁to C₆-alkyl), —CH₂OP(O)(OR²⁰)(OR²¹), —SO₂NR²⁴R²⁵; or —NR²⁴R²⁵, with theproviso that R² and R⁶ are not both Cl when R¹ is an aromatic ring, X²and X³ are CH, and R¹¹ is H; or a pharmaceutically acceptable salt,ester, single stereoisomer, mixture of stereoisomers, or a tautomerthereof.
 8. The compound of claim 7, wherein: (a) X² and X³ are CH; or(b) X² is CH and X³ is N.
 9. The compound of claim 7, wherein: (a) R³,R⁴, and R⁵ are H.
 10. The compound of claim 7, wherein: (a) R³, R⁴, andR⁵ are independently H, Cl, F, CH₃, or CF₃; (b) R² is selected from H,Cl, F, or CH₃; (c) R⁶ is selected from H, Br, Cl, F, or CF₃; and/or (d)R¹¹ is selected from H and halogen; optionally, wherein R¹¹ is 3-fluoro.11. The compound of claim 7, wherein R¹ is selected from:


12. The compound of claim 7, wherein the compound is selected fromcompounds (1a), (1b), (1c), (1d), (1e), (1f), (1g), (1h), (1i), (1j),(1k), (1l), (1m), and (1n), or a pharmaceutically acceptable salt, anester, a single stereoisomer, a mixture of stereoisomers, or a tautomerthereof


13. A pharmaceutical composition comprising a therapeutically effectiveamount of the compound of any one of claim 1 and a pharmaceuticallyacceptable carrier.
 14. A method of treating chemical dependency on asubstance or condition of addiction comprising administering apharmaceutical composition of claim 13; optionally, wherein thesubstance or condition of addiction is selected from the groupconsisting of alcohol, nicotine, cocaine, opiates, amphetamines, andcompulsive eating.
 15. A method of treating compulsive eating disordercomprising administering to a human patient a pharmaceutical compositionof claim
 13. 16. A method of treating anxiety comprising administeringto a human patient a pharmaceutical composition of claim
 13. 17. Apharmaceutical composition comprising a therapeutically effective amountof the compound of any one of claim 7 and a pharmaceutically acceptablecarrier.
 18. A method of treating chemical dependency on a substance orcondition of addiction comprising administering a pharmaceuticalcomposition of claim 17; optionally, wherein the substance or conditionof addiction is selected from the group consisting of alcohol, nicotine,cocaine, opiates, amphetamines, and compulsive eating.
 19. A method oftreating compulsive eating disorder comprising administering to a humanpatient a pharmaceutical composition of claim
 17. 20. A method oftreating anxiety comprising administering to a human patient apharmaceutical composition of claim 17.